ZusammenfassungDurch eine Gesetzesänderung im Dezember 2019 ist im Rahmen von Strafermittlungsverfahren nunmehr der Einsatz des „Forensic DNA Phenotyping“, d. h. von Technologien zur Vorhersage von Haut-, Haar- und Augenfarbe sowie biologischem Alter, erlaubt. Dieser Beitrag diskutiert die Verlässlichkeit, Nützlichkeit und Legitimität von solchen Erweiterten DNATechnologien und damit die Rahmenbedingungen ihres Einsatzes in Deutschland. Dabei wird aufgezeigt wie kompliziert, fehleranfällig, voraussetzungsreich, anspruchsvoll und heikel der Einsatz dieser Technologien in Ermittlungen sein kann, wenn nicht entsprechende Vorkehrungen getroffen werden, und wenn sie nicht (...) auf umsichtig begleitete Einzelfälle beschränkt bleiben. Aufbauend auf dieser Analyse werden schließlich Maßnahmen für die Anwendung und Regulierung Erweiterter DNA-Technologien in Deutschland vorgeschlagen. (shrink)

Wasted Chances? The Current Political Debate on DNA Phenotyping and Biogeographical Ancestry Analysis in Criminal Investigation in Germany. This paper discusses diverse understandings of ‘responsible science’ in heated political debates. It takes a current public debate around a German law amendment draft concerning the use of novel forensic genetic techniques, namely DNA‐phenotyping and biogeographical ancestry analysis, as an example. A distinction is being made between an understanding that emphasizes scientific debate and precision, and another one that focuses on political agency. (...) The paper also addresses the question whether and how science studies scholars, given their depth of expertise in the analysis of complex problems spanning disciplinary boundaries, should contribute to national debates in policy fields where no such dialogue exists yet. (shrink)

There is a concern according to which analyzing crime scene DNA to determine biogeographic origin and skin color of suspects can lead to discrimination against minority populations. This article summarizes and explains some of those parts of the investigation process that can give rise to discrimination. The second part of the paper offers an analysis of the notion of discrimination and presents different accounts of the exact ground of its moral wrongness. As it will emerge, these different accounts lead to (...) different assessments of the use of DNA phenotype analyses in police investigations. -/- ----- Dieser Beitrag befasst sich mit der Befürchtung, dass eine Erweiterung der DNA-Analyse von Tatortspuren für Zwecke der Polizeiarbeit zu Diskriminierungen führen wird. Diese Erwartung bezieht sich insbesondere auf die Ermittlung der sogenannten biogeografischen Abstammung und der Hautschattierung. In dieser Untersuchung werden einige Stellen im Ermittlungsprozess, an denen auf Grundlage solcher Analysen Diskriminierungspotential auftreten könnte, zunächst gesammelt und dargelegt. Im zweiten Teil wird dann der Diskriminierungsbegriff genauer beleuchtet. Dabei wird sich zeigen, dass verschiedene Positionen zu der Frage, was genau eine Diskriminierung moralisch problematisch macht, zu unterschiedlichen Einschätzungen der DNA-Phänotypisierung in der Polizeiarbeit führen. (shrink)

DNA topoisomerases, capable of manipulating DNA topology, are ubiquitous and indispensable for cellular survival due to the numerous roles they play during DNA metabolism. As we review here, current structural approaches have revealed unprecedented insights into the complex DNA‐topoisomerase interaction and strand passage mechanism, helping to advance our understanding of their activities in vivo. This has been complemented by single‐molecule techniques, which have facilitated the detailed dissection of the various topoisomerase reactions. Recent work has also revealed the importance of topoisomerase (...) interactions with accessory proteins and other DNA‐associated proteins, supporting the idea that they often function as part of multi‐enzyme assemblies in vivo. In addition, novel topoisomerases have been identified and explored, such as topo VIII and Mini‐A. These new findings are advancing our understanding of DNA‐related processes and the vital functions topos fulfil, demonstrating their indispensability in virtually every aspect of DNA metabolism. (shrink)

DNA barcodes, like traditional sources of taxonomic information, are potentially powerful heuristics in the identification of described species but require mindful analytical interpretation. The role of DNA barcoding in generating hypotheses of new taxa in need of formal taxonomic treatment is discussed, and it is emphasized that the recursive process of character evaluation is both necessary and best served by understanding the empirical mechanics of the discovery process. These undertakings carry enormous ramifications not only for the translation of DNA sequence (...) data into taxonomic information but also for our comprehension of the magnitude of species diversity and its disappearance. This paper examines the potential strengths and pitfalls of integrating DNA sequence data, specifically in the form of DNA barcodes as they are currently generated and analyzed, with taxonomic practice. (shrink)

The pedagogical function of science teaching may benefit from an analysis of the historical-epistemic dimension, without neglecting the socio-political context in which a given research was carried out. In the case of DNA structure, the background of its discovery is particularly complex. Starting from the analysis of some papers, the view on the circumstances that led to their drafting broadens. We try to answer the fundamental question for any educator: why teach all that? Ethics issues are related to the general (...) organisation of research, increasingly focused on speed and competition. Even teaching is affected by these dynamics, not only in higher education, but also at secondary level; students should be made aware of this trend. The history of science could therefore favour a more general awareness. _SUNTO_ La funzione pedagogica dell’insegnamento scientifico può trarre vantaggio da un’analisi della dimensione storico-epistemica, senza trascurare il contesto socio-politico nel quale una determinata ricerca è stata condotta. Nel caso della struttura del DNA, i retroscena della sua scoperta sono particolarmente complessi. Dopo l’analisi di alcuni articoli, si allarga gradualmente la vista sulle circostanze che hanno condotto alla loro stesura. Si cerca di rispondere a una domanda fondamentale per ogni educatore: perché insegnare tutto ciò? Le questioni etiche riguardano l’organizzazione generale della ricerca, sempre più tesa alla velocità e alla competizione. Persino l’insegnamento è influenzato da dinamiche simili, non solo in ambito accademico, ma anche a livello secondario; gli studenti dovrebbero essere a conoscenza di questa tendenza. La storia della scienza può dunque favorire una maggiore consapevolezza. (shrink)

Through analysis of film sequences focusing on DNA in two British Broadcasting Corporation nonfiction science television programs, Wonders of Life and Bang! Goes the Theory, first broadcast in 2013, contrasting “religious” and “secular” representations of science are identified. In the “religious” portrayal, immutable scientific knowledge is revealed to humanity by nature with minimal human intervention. Science provides a creation story, “explanatory omnicompetence,” and makes life existentially meaningful. In the “secular” portrayal, scientific knowledge is changeable; is produced through technical skill in (...) expert communities; and is ambiguous, potentially positive and negative for society. Television representations of science affect audience understandings, and this is particularly the case for nonfiction representations of science, as they are likely to be “taken more seriously” than fictional representations. The consequences of the “religious” representation of science are discussed, and it is argued that a widespread understanding of science as presented in the religious portrayal would negatively impact democracy. (shrink)

We define DNA sequence by a bottom-up approach, starting with a real sequence from an actual biological sample. By providing axioms for notions of string, substring and strand, we formally define a DNA sequence, and a DNA molecule as composed of two antiparallel strands. We note that a sequence is a kind of group in which each member stands a certain relation to every other. The spatial aspects of a DNA sequence are also described.

DNA methylation can be considered a component of epigenetic memory with a critical role during embryo development, and which undergoes dramatic reprogramming after fertilization. Though it has been a focus of research for many years, the reprogramming mechanism is still not fully understood. Recent results suggest that absence of maintenance at DNA replication is a major factor, and that there is an unexpected role for TET3-mediated oxidation of 5mC to 5hmC in guarding against de novo methylation. Base-resolution and genome-wide profiling (...) methods are enabling more comprehensive assessments of the extent to which ART might impair DNA methylation reprogramming, and which sequence elements are most vulnerable. Indeed, as we also review here, studies showing the effect of culture media, ovarian stimulation or embryo transfer on the methylation pattern of embryos emphasize the need to face ART-associated defects and search for strategies to mitigate adverse effects on the health of ART-derived children. DNA methylation, critical for embryo development, suffers significant changes after fertilization, including demethylation, remethylation and TET3-mediated oxidation of 5 mC to 5 hmC. In addition to infertility and environmental insults, ART could impact DNA methylation and ART related consequences in the offspring have been reported. (shrink)

DNA supercoiling is one of the mechanisms that can help unlinking of newly replicated DNA molecules. Although DNA topoisomerases, which catalyze the strand passing of DNA segments through one another, make the unlinking problem solvable in principle, it remains difficult to complete the process that enables the separation of the sister duplexes. A few different mechanisms were developed by nature to solve the problem. Some of the mechanisms are very intuitive while the others, like topology simplification by type II DNA (...) topoisomerases and DNA supercoiling, are not so evident. A computer simulation and analysis of linked sister plasmids formed inEscherichia colicells with suppressed topoisomerase IV suggests an insight into the latter mechanism. (shrink)

The regulation of DNA replication is a fascinating biological problem both from a mechanistic angle—How is replication timing regulated?—and from an evolutionary one—Why is replication timing regulated? Recent work has provided significant insight into the first question. Detailed biochemical understanding of the mechanism and regulation of replication initiation has made possible robust hypotheses for how replication timing is regulated. Moreover, technical progress, including high‐throughput, single‐molecule mapping of replication initiation and single‐cell assays of replication timing, has allowed for direct testing of (...) these hypotheses in mammalian cells. This work has consolidated the conclusion that differential replication timing is a consequence of the varying probability of replication origin initiation. The second question is more difficult to directly address experimentally. Nonetheless, plausible hypotheses can be made and one—that replication timing contributes to the regulation of chromatin structure—has received new experimental support. (shrink)

The nuclear pore complex (NPC) is emerging as a center for recruitment of a class of “difficult to repair” lesions such as double‐strand breaks without a repair template and eroded telomeres in telomerase‐deficient cells. In addition to such pathological situations, a recent study by Su and colleagues shows that also physiological threats to genome integrity such as DNA secondary structure‐forming triplet repeat sequences relocalize to the NPC during DNA replication. Mutants that fail to reposition the triplet repeat locus to the (...) NPC cause repeat instability. Here, we review the types of DNA lesions that relocalize to the NPC, the putative mechanisms of relocalization, and the types of recombinational repair that are stimulated by the NPC, and present a model for NPC‐facilitated repair. (shrink)

Science; Ethics; Politics; Beyond recombinant dna.

Recent studies based on next‐generation DNA sequencing have revealed that the female inactive X chromosome is replicated in a rapid, unorganized manner, and undergoes increased rates of mutation. These observations link the organization of DNA replication timing to gene regulation on one hand, and to the generation of mutations on the other hand. More generally, the exceptional biology of the inactive X chromosome highlights general principles of genome replication. Cells may control replication timing by a combination of intrinsic replication origin (...) properties, local chromatin states and global levels of replication factors, leading to a functional separation between the activity of genes and their mutation. (shrink)

This paper focuses on the question of whether DNA patents help or hinder scientific discovery and innovation. While DNA patents create a wide variety of possible benefits and harms for science and technology, the evidence we have at this point in time supports the conclusion that they will probably promote rather than hamper scientific discovery and innovation. However, since DNA patenting is a relatively recent phenomena and the biotechnology industry is in its infancy, we should continue to gather evidence about (...) the effects of DNA patenting on scientific innovation and discovery as well the economic, social, and legal conditions relating to intellectual property in biotechnology. We should give the free market, the courts, researchers, and patent offices a chance to settle issues related to innovation and discovery, before we seek legislative remedies, since new laws proposed at this point would lack adequate foresight and could do more harm than good. However, we should be open to new laws or regulations on DNA patents if they are required to in order to deal with some of the biases and limitations of the free market. (shrink)

DNA methylation is a repressive epigenetic mark vital for normal development. Recent studies have uncovered an unexpected role for the DNA methylome in ensuring the correct targeting of the Polycomb repressive complexes throughout the genome. Here, we discuss the implications of these findings for cancer, where DNA methylation patterns are widely reprogrammed. We speculate that cancer‐associated reprogramming of the DNA methylome leads to an altered Polycomb binding landscape, influencing gene expression by multiple modes. As the Polycomb system is responsible for (...) the regulation of genes with key roles in cell fate decisions and cell cycle regulation, DNA methylation induced Polycomb mis‐targeting could directly drive carcinogenesis and disease progression.Editor's suggested further reading in BioEssays Unmasking risk loci: DNA methylation illuminates the biology of cancer predisposition Abstract. (shrink)

For nearly two decades, nonengineered human DNA was patented without challenge. The US Supreme Court recently agreed that many of those patents do not fit accurately into any currently accepted scheme of intellectual property protection. One should consider: whether DNA fits into other forms of property protection (land, moveables, chattels, etc.); whether DNA warrants a new and unique form of property protection, or whether DNA belongs to the class of objects generally considered to be as “the commons.” Current schemes of (...) patent protection for genes are entirely new, unwarranted by precedent, and utterly aberrant in applying the law of patent. Nonetheless, it bears examining how intellectual property schemes might serve as guidance for new forms of intellectual property protection for genes, if indeed those genes fit into classical dimensions of intellectual property. Private ownership of property has emerged as the dominant legal institution covering modes of possession. (shrink)

Emerging evidence suggests that DNA topology plays an instructive role in cell fate control through regulation of gene expression. Transcription produces torsional stress, and the resultant supercoiling of the DNA molecule generates an array of secondary structures. In turn, local DNA architecture is harnessed by the cell, acting within sensory feedback mechanisms to mediate transcriptional output. MYC is a potent oncogene, which is upregulated in the majority of cancers; thus numerous studies have focused on detailed understanding of its regulation. Dissection (...) of regulatory regions within the MYC promoter provided the first hint that intimate feedback between DNA topology and associated DNA remodeling proteins is critical for moderating transcription. As evidence of such regulation is also found in the context of many other genes, here we expand on the prototypical example of the MYC promoter, and also explore DNA architecture in a genome-wide context as a global mechanism of transcriptional control. Torsional stress, and supercoiling generated by transcription, shape the topology of DNA. Furthermore, the resultant secondary DNA structures and their interacting partners provide feedback to regulate gene expression. Emerging evidence suggests these mechanisms, identified through analysis of the MYC promoter, are applicable genome-wide. (shrink)

DNA profiling is a well-established technology for use in the criminal justice system, both in courtrooms and elsewhere. The fact that DNA profiles are based on non-coding DNA and do not reveal details about the physical appearance of an individual has contributed to the acceptability of this type of evidence. Its success in criminal investigation, combined with major innovations in the field of genetics, have contributed to a change of role for this type of evidence. Nowadays DNA evidence is not (...) merely about identification, where trace evidence is compared to a sample taken from a suspect. An ever-growing role is anticipated for DNA profiling as an investigative tool, a technique aimed at generating a suspect where there is none. One of these applications is the inference of visible traits. As this article will show, racial classifications are at the heart of this application. The Netherlands and its legal regulation of 'externally visible traits' will serve as an example. It will be shown that, to make this technology work, a large number of actors has to be enrolled and their articulations invited. This indicates that instead of a 'silent witness', a DNA profile should rather be seen as an 'articulate collective'. Based on two cases, I argue that the normativity of visible traits is context-dependent. Taking into account the practices in which technology is put to use alerts us to novel ethical questions raised by their application. (shrink)

Under the terms of the UN Convention on the Rights of the Child, which Australia has ratified, children have a right to know who their genetic parents are. As a result, we have a duty to establish these facts and to make this information available for children to access should they wish to know. Introducing mandatory DNA testing of newborns and their alleged genetic parents is one viable option to ensure that this information is available for children to access. Indeed, (...) it may be the only viable option to address childrens' right to the fulfilment of Article 7 of the CRC. There are a number of benefits to obtaining this benefit for children. For one, mandatory DNA testing could solve all disputed paternity cases and finalise them early in the lives of children, thus making life more financially secure for those children in the long term. This could reduce or eliminate the need for fathers to secretly carry out DNA tests in order to disestablish paternity. The large number of benefits gained from identifying genetic parents for children and the small possible risks that they may suffer when this information is withheld give us good reasons to support mandatory DNA testing. (shrink)

Die folgenden Analysen stellen einen Versuch dar, von der Philosophie her Kunst zu verstehen d.h. zu deuten. Die Epoche, da der Umgang mit der Kunst sich auf ein ästhetisches Betrach ten reduzierte, ist zu Ende gegangen, was allerdings nicht besagt, daß wir nicht immer wieder in sie zurückfallen können, weil diese Art des Zugangs sich unmittelbar anzubieten scheint, das Nächst liegende ist, an den Betrachter die geringsten Anforderungen stellt. Die Überwindung der "ästhetischen" Kunstbetrachtung ge schieht in dem Augenblick, da (...) wir die Kunst ernst nehmen, in ihr eine Sprache sehen, in der nicht auf gewöhnliche Weise Dinge und Situationen einfach genannt werden, sondern die Art des herrschenden Weltbezuges selbst offenbar wird, allerdings in einer Art Hieroglyphenschrift, die der Deutung bedarf um versteh bar zu werden. Für diesen Weltbezug - der sowohl den Bezug zwischen den Menschen, wie den zum nichtmenschlichen Seienden und den Bezug des Menschen zu sich selbst träg- wurde der Terminus Nähe eingeführt. Nähe heißt hier also keineswegs der räumliche Abstand zwischen Dingen, die be stimmte Distanz, die meßbar und in Zahlen ausdrückbar ist, sondern der immer unmeßbar bleibende Grund des Weltverhält nisses, der eine bestimmte Epoche auszeichnet. (shrink)

The aim of this paper is to explain the emergence and use of DNA fingerprinting technology in India, noting the specific concerns faced by the Indian Legal System related to the use of this novel forensic technology in the justice process. Furthermore, the proposed construction of a National DNA Data Bank is discussed taking into consideration the challenges faced by the government in legislating the DNA Bill into law. A critical analysis of the DNA Technology (Use and Application) Regulation Bill, (...) 2019 is provided to throw light upon many ethical, social, and legal issues that need to be addressed before the operationalization of the Bill to ensure that this technology is governed democratically to protect the civil liberties of citizens. (shrink)

Abstract6‐methyladenine (6mA) is fairly abundant in nuclear DNA of basal fungi, ciliates and green algae. In these organisms, 6mA is maintained near transcription start sites in ApT context by a parental‐strand instruction dependent maintenance methyltransferase and is positively associated with transcription. In animals and plants, 6mA levels are high only in organellar DNA. The 6mA levels in nuclear DNA are very low. They are attributable to nucleotide salvage and the activity of otherwise mitochondrial METTL4, and may be considered as a (...) price that cells pay for adenine methylation in RNA and/or organellar DNA. Cells minimize this price by sanitizing dNTP pools to limit 6mA incorporation, and by converting 6mA that has been incorporated into DNA back to adenine. Hence, 6mA in nuclear DNA should be described as an epigenetic mark only in basal fungi, ciliates and green algae, but not in animals and plants. (shrink)

Ancient DNA has been discovered in many types of preserved biological material, including bones, mummies, museum skins, insects in amber and plant fossils, and has become an important research tool in disciplines as diverse as archaeology, conservation biology and forensic science. In archaeology, ancient DNA can contribute both to the interpretation of individual sites and to the development of hypotheses about past populations. Site interpretation is aided by DNA‐based sex typing of fragmentary human bones, and by the use of genetic (...) techniques to assess the degree of kinship between the remains of different individuals. On a broader scale, population migrations can be traced by studying genetic markers in ancient DNA, as in recent studies of the colonisation of the Pacific islands, while ancient DNA in preserved plant remains can provide information on the development of agriculture. (shrink)

The sciences of genetics and genomics are revealing more all the time regarding our statuses as individuals relative to our particular genomes. Geographical isolation is presumably the greatest factor in allowing for populations of a species to change genetically over time, in response to environmental pressures and genetic drift accelerated by the mechanism of sexual reproduction. In order to develop a robust account of what rights individual members of the human species might have to either their own particular DNA or (...) the human genome in general, one need to explain the relations between individuals and species in regards to deoxyribonucleic acid (DNA). The fact that genes carry over from species to species does not mean that those genes are completely identical across all species. Laws and regulations exist that govern the use of human tissues and property rights over their products. (shrink)

This paper assesses the effect of DNA barcoding—the use of informative genetic markers to identify and discriminate between species—on taxonomy. Throughout, we interpret this in terms of _varipraxis_, a concept we introduce to make sense of the treatment of biological variation by scientists and other practitioners. From its inception, DNA barcoding was criticised for being reductive, in attempting to replace multiple forms of taxonomic evidence with just one: DNA sequence variation in one or a few indicative genes. We show, though, (...) how DNA barcoding has not narrowed or reduced taxonomy in the way it was projected to. We examine the development and implementation of DNA barcoding across three kingdoms of life: animals, plants, and protists. Through this, we demonstrate that for DNA barcoding to work, the range of acceptable intra-specific variation needs to be demarcated from variation deemed to be characteristic of inter-specific differences. Consequently, biological processes responsible for particular patterns of variation need to be investigated and understood. This encourages an integrative disposition towards understanding and explaining the evolutionary processes affecting the rate and nature of change at the nucleotide level. We detail how the impact of DNA barcoding has manifested differently across the three kingdoms we examine, assessing this in terms of the ontological commitments that are held and instantiated in practice. Based on this evaluation, we consider the problem of studying multi-kingdom communities, and assess the consequences of our analysis for understanding classification and taxonomy. (shrink)

DNA helicases catalyze the disruption of the hydrogen bonds that hold the two strands of double‐stranded DNA together. This energy‐requiring unwinding reaction results in the formation of the single‐stranded DNA required as a template or reaction intermediate in DNA replication, repair and recombination. A combination of biochemical and genetic studies have been used to probe and define the roles of the multiple DNA helicases found in E. coli. This work and similar efforts in eukaryotic cells, although far from complete, have (...) established that DNA helicases are essential components of the machinery that interacts with the DNA molecule. (shrink)

In its last round of publications in September 2012, the Encyclopedia Of DNA Elements (ENCODE) assigned a biochemical function to most of the human genome, which was taken up by the media as meaning the end of ‘Junk DNA’. This provoked a heated reaction from evolutionary biologists, who among other things claimed that ENCODE adopted a wrong and much too inclusive notion of function, making its dismissal of junk DNA merely rhetorical. We argue that this criticism rests on misunderstandings concerning (...) the nature of the ENCODE project, the relevant notion of function and the claim that most of our genome is junk. We argue that evolutionary accounts of function presuppose functions as ‘causal roles’, and that selection is but a useful proxy for relevant functions, which might well be unsuitable to biomedical research. Taking a closer look at the discovery process in which ENCODE participates, we argue that ENCODE’s strategy of biochemical signatures successfully identified activities of DNA elements with an eye towards causal roles of interest to biomedical research. We argue that ENCODE’s controversial claim of functionality should be interpreted as saying that 80 % of the genome is engaging in relevant biochemical activities and is very likely to have a causal role in phenomena deemed relevant to biomedical research. Finally, we discuss ambiguities in the meaning of junk DNA and in one of the main arguments raised for its prevalence, and we evaluate the impact of ENCODE’s results on the claim that most of our genome is junk. (shrink)

Over 30 million people worldwide have taken a commercial at-home DNA test, because they were interested in their genetic ancestry, disease predisposition or inherited traits. Yet, these consumer DNA data are also increasingly used for a very different purpose: to identify suspects in criminal investigations. By matching a suspect’s DNA with DNA from a suspect’s distant relatives who have taken a commercial at-home DNA test, law enforcement can zero in on a perpetrator. Such forensic use of consumer DNA data has (...) been performed in over 200 criminal investigations. However, this practice of so-called investigative genetic genealogy raises ethical concerns. In this paper, we aim to broaden the bioethical analysis on IGG by showing the limitations of an individual-based model. We discuss two concerns central in the debate: privacy and informed consent. However, we argue that IGG raises pressing ethical concerns that extend beyond these individual-focused issues. The very nature of the genetic information entails that relatives may also be affected by the individual customer’s choices. In this respect, we explore to what extent the ethical approach in the biomedical genetic context on consent and consequences for relatives can be helpful for the debate on IGG. We argue that an individual-based model has significant limitations in an IGG context. The ethical debate is further complicated by the international, transgenerational and commercial nature of IGG. We conclude that IGG should not only be approached as an individual but also—and perhaps primarily—as a collective issue. There are no data in this work. (shrink)

The debate over recombinant DNA research is a unique event, perhaps a turning point, in the history of science. For the first time in modern history there has been widespread public discussion about whether and how a promising though potentially dangerous line of research shall be pursued. At root the debate is a moral debate and, like most such debates, requires proper assessment of the facts at crucial stages in the argument. A good deal of the controversy over recombinant DNA (...) research arises because some of the facts simply are not yet known. There are many empirical questions we would like to have answered before coming to a decision-questions about the reliability of proposed containment facilities, about the viability of enfeebled strains of E. coli, about the ways in which pathogenic organisms do their unwelcome work, and much more. But all decisions cannot wait until the facts are available; some must be made now. It is to be expected that people with different hunches about what the facts will turn out to be will urge different decisions on how recombinant DNA research should be regulated. However, differing expectations about the facts have not been the only fuel for controversy. A significant part of the current debate can be traced to differences over moral principles. Also, unfortunately, there has been much unnecessary debate generated by careless moral reasoning and a failure to attend to the logical structure of some of the moral arguments that have been advanced. (shrink)

In his keynote address at a recent Intelligent Design (ID) conference at Biola University, ID leader William Dembski began by quoting "a well-known ID sympathizer" whom he had asked to assess the current state of the ID movement. Dembski explained that he had asked because, "after some initial enthusiasm on his part three years ago, his interest seemed to have flagged" (Dembski 2002). The sympathizer replied that..

Methylation of DNA plays an important role in the control of gene expression in higher eukaryotes. This is largely achieved by the packaging of methylated DNA into chromatin structures that are inaccessible to transcription factors and other proteins. Methylation involves the addition of a methyl group to the 5‐position of the cytosine base in DNA, a reaction catalysed by a DNA (cytosine‐5) methyltransferase. This reaction occurs in nuclear replication foci where the chromatin structure is loosened for replication, thereby allowing access (...) to methyltransferases. Partly as a result of their recognising the presence of a methylcytosine on the parental strand following replication, these large enzymes are able to maintain the distribution of methyl groups along the DNA of somatic cells and, thereby, maintain tissue‐specific patterns of gene expression. (shrink)

Those objecting to human DNA patenting frequently do so on the grounds that the practice violates or threatens human dignity. For example, from 1993 to 1994, more than thirty organizations representing indigenous peoples approved formal declarations objecting to the National Institutes of Health's bid to patent viral DNA taken from subjects in Papua New Guinea and the Solomon Islands. Although these were not patents on human DNA, the organizations argued that the patents could harm and exploit indigenous peoples and violate (...) their cultural values. NIH eventually dropped one of its patent applications.On May 18, 1995, 180 religious leaders, led by biotechnology critic Jeremy Rifkin, held a press conference objecting to DNA patenting in Washington, D.C. In their “Joint Appeal against Human and Animal Patenting,” these leaders decried any attempt to patent nature. Some of the more outspoken members of the Joint Appeal likened DNA patenting to slavery, while others objected to treating human beings as marketable commodities. In his recent book, The Biotech Century, Rifkin rehashed the objections to DNA patenting voiced by members of the Joint Appeal. (shrink)

The model of DNA-histones has the following elements: The hydrogen bonds between the complementary nucleotide bases function as informational gates. When the electrons π of one nucleotide base are excited, an exchange of protons is produced between the two complementary bases. The result is the displacement of the conjugated double bonds which facilitates the inter-molecular transmission of the electronic wave of excitation by electro-magnetic coupling. Each triplet of nucleotide bases of DNA fixes one definite amino acid . Between the nucleotide (...) bases and the amino acids there are constituted informational gates, which ensure the circulation of the electronic wave of excitation. An input signal molecule arrives at the receiver gene and unleashes the activity of the enzymes which introduce in the DNA-histones system the electronic wave of excitation. The electronic wave of excitation arises as a result of the break of the high-energy bonds of ATP. Then, the electronic excitation is transmitted to the productor gene where it represents the signal for starting the synthesis of the mRNA.Le modèle de système ADN-Histone a les éléments suivants: Les liaisons d'hydrogène entre les bases nucléotidiques complémentaires fonctionnent comme des portes informationnelles. Quand les électrons π d'une base nucléotidique sont excités, il se produit un échange de protons entre les bases complémentaires. Le résultat est un déplacement des doubles liaisons conjugées qui facilite la transmission de l'onde d'excitation électronique par un couplage électromagnétique. Chaque triplet de bases nucléotidiques de l'ADN fixe un certain amino-acide . Entre les bases nucléodiques et les amino-acides se constituent des portes informationnelles qui assurent la circulation de l'onde d'excitation dlectronique. Une molécule signal d'entrée arrive au gène récepteur et déclenche l'activité des enzymes qui introduisent dans le système ADN-histone l'excitation électronique. L'excitation électronique apparait comme résultat de la rupture des liaisons de haute énergie del' ATP. l'Onde d'excitation électronique est transmise au gène producteur, où elle rdprésente le signal pour faire commencer la synthèse de l'ARNm.Das Modell des DNS-Histonen Systems weist folgende Elemente auf: Die Wasserstoffbindungen zwischen den komplementäaren Nukleotidbasen funktionieren wie informationale Pforten. Wenn die π Elektronen einer Nukleotidbase erregt werden, ensteht ein Protonenwechsel zwischen den Komplementären Basen. Das Ergebnis ist eine Verschiebung der konjugierten Doppelbindungen, die die Weiterleitung der elektronischen Erregungswelle durch eine elektromagnetische Kupplung erleichtert. Jedes Nukleotidbasentriplett der DNS fixiert eine bestimmte Aminosäure . Zwischen den Nukelotidbasen und den Aminosäuren entstehen Informationspforten, welche den Umlauf der elektronischen Erregungswelle sichern. Ein Eintrittsignal Moleküul gelangt zur Rezeptorgen und löst die Aktivität von Enzymen aus, welche die elektronische Erregungswelle in das DNS-Histonen System einführen werden. Die elektronische Erregungswelle erscheint als Ergebnis der Spaltung der hochenergetischen Bindungen des ATP-s. Die elektronische Erregungswelle wird alsdann zur Produktorgen weitergeleitet, wo sie das Signal zum Beginn der Synthese der mRNS darstellt. (shrink)

The repair of chromosomal double‐strand breaks (DSBs) by homologous recombination is essential to maintain genome integrity. The key step in DSB repair is the RecA/Rad51‐mediated process to match sequences at the broken end to homologous donor sequences that can be used as a template to repair the lesion. Here, in reviewing research about DSB repair, I consider the many factors that appear to play important roles in the successful search for homology by several homologous recombination mechanisms.

DNA methylation is a repressive epigenetic modification that is essential for development and its disruption is widely implicated in disease. Yet, remarkably, ablation of DNA methylation in transgenic mouse models has limited impact on transcriptional states. Across multiple tissues and developmental contexts, the predominant transcriptional signature upon loss of DNA methylation is the de‐repression of a subset of germline genes, normally expressed in gametogenesis. We recently reported loss of de novo DNA methyltransferase DNMT3B resulted in up‐regulation of germline genes and (...) impaired syncytiotrophoblast formation in the murine placenta. This defect led to embryonic lethality. We hypothesize that de‐repression of germline genes in the Dnmt3b knockout underpins aspects of the placental phenotype by interfering with normal developmental processes. Specifically, we discuss molecular mechanisms by which aberrant expression of the piRNA pathway, meiotic proteins or germline transcriptional regulators may disrupt syncytiotrophoblast development. (shrink)

Recombinant DNA technology is an essential area of life engineering. The main aim of research in this field is to experimentally explore the possibilities of repairing damaged human DNA, healing or enhancing future human bodies. Based on ethnographic research in a Czech biochemical laboratory, the article explores biotechnological corporealities and their specific ontology through dealings with bio-objects, the bodywork of scientists. Using the complementary concepts of utopia and heterotopia, the text addresses the situation of bodies and bio-objects in a laboratory. (...) Embodied utopias are analyzed as material semiotic phenomena that are embodied by scientists in their visions and emotions and that are related to potential bodies and to future, not-yet-actualized embodiments. As a counterpart to this, the text explores embodied heterotopias, which are always the other spaces, like biotechnological bio-objects that are simulated in computers or stored in special solutions. (shrink)

Eminent scientists are well-placed to bring the novel works of others, even if not in their own areas of expertise, to general attention. In so doing, they may be able to extend original accounts or introduce new terminologies, but they are basically messengers, not innovators. In the 1940s an evolutionary theory of biological aging was explained by Peter Medawar, and informational concepts relating to DNA were explained by Erwin Schrödinger. Both explanations were eventually traced back to the Victorian polymath Samuel (...) Butler—one by Medawar’s research associate Alex Comfort, and the other, albeit indirectly, by Schrödinger himself. In his time Butler’s works were too erudite for general readers and too laden with populist jargon for contemporary experts to take seriously. However, today it appears counterfactually plausible that an early acceptance of his ideas would have greatly quickened the pace of research. (shrink)

As nations strengthen borders and restrict refugee admissions, national security officials are screening for fraudulent nationality claims. One tool to investigate nationality claims is DNA testing, either for claimed relationships or for ancestral origins. At the same time, the plight of global statelessness leaves millions without documentation of their nationality, and DNA testing might be the only recourse to provide evidence of heritage or relationships. DNA testing has been used sparsely to date to determine ancestral origin as a proxy for (...) nationality but could increase as border controls tighten. Given the historic lessons in eugenics and the potential for misuse of personal genetic information, it is essential to consider the ethical parameters in order to guide the implementation of genetic data for such purposes. Here, we break down examples of the use of DNA testing for nationality, and the risks and benefits of genetic testing for this purpose. Important ethical considerations discussed include (1) empowerment of stateless individuals with evidence for citizenship proceedings; (2) imprecise correlation between genetic heritage and nationality; (3) effective protection of state interests; and (4) practicalities of DNA testing. (shrink)

DNA with a curved trajectory of its helix axis is called bent DNA, or curved DNA. Interestingly, biologically important DNA regions often contain this structure, irrespective of the origin of DNA. In the last decade, considerable progress has been made in clarifying one role of bent DNA in prokaryotic transcription and its mechanism of action. However, the role of bent DNA in eukaryotic transcription remains unclear. Our recent study raises the possibility that bent DNA is implicated in the “functional packaging” (...) of transcriptional regulatory regions into chromatin. In this article, I review recent progress in bent DNA research in eukaryotic transcription, and summarize the history of bent DNA research and several subjects relevant to this theme. Finally, I propose a hypothesis that bent DNA structures that mimic a negative supercoil, or have a right‐handed superhelical writhe, organize local chromatin infrastructure to help the very first interaction between cis‐acting DNA elements and activators that trigger transcription. BioEssays 23:708–715, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

The DNA‐passage activity of topoisomerase II accidentally produces DNA knots and interlinks within and between chromatin fibers. Fortunately, these unwanted DNA entanglements are actively removed by some mechanism. Here we present an outline on DNA knot formation and discuss recent studies that have investigated how intracellular DNA knots are removed. First, although topoisomerase II is able to minimize DNA entanglements in vitro to below equilibrium values, it is unclear whether such capacity performs equally in vivo in chromatinized DNA. Second, DNA (...) supercoiling could bias topoisomerase II to untangle the DNA. However, experimental evidence indicates that transcriptional supercoiling of intracellular DNA boosts knot formation. Last, cohesin and condensin could tighten DNA entanglements via DNA loop extrusion (LE) and force their dissolution by topoisomerase II. Recent observations indicate that condensin activity promotes the removal of DNA knots during interphase and mitosis. This activity might facilitate the spatial organization and dynamics of chromatin. (shrink)

In this brief report, the authors argue that while a lot of concerns about forensic DNA databases have been raised using arguments from biomedical ethics, these databases are used in a complete different context from other biomedical tools. Because they are used in the struggle against crime, the decision to create or store a genetic profile cannot be left to the individual. Instead, this decision is made by officials of a society. These decisions have to be based on a policy (...) that is the concretisation of some of society's most fundamental ideas about its own nature and function. Individuals wanting to influence these decisions have to try to influence this policy, within the bounds of a state's own self-concept. This article is an attempt to reorient the discussion about forensic DNA databases from a biomedical debate to a more political–philosophical one. (shrink)

Here, the emerging data on DNA G‐quadruplexes (G4s) as epigenetic modulators are reviewed and integrated. This concept has appeared and evolved substantially in recent years. First, persistent G4s (e.g., those stabilized by exogenous ligands) were linked to the loss of the histone code. More recently, transient G4s (i.e., those formed upon replication or transcription and unfolded rapidly by helicases) were implicated in CpG island methylation maintenance and de novo CpG methylation control. The most recent data indicate that there are direct (...) interactions between G4s and chromatin remodeling factors. Finally, multiple findings support the indirect participation of G4s in chromatin reshaping via interactions with remodeling‐related transcription factors (TFs) or damage responders. Here, the links between the above processes are analyzed; also, how further elucidation of these processes may stimulate the progress of epigenetic therapy is discussed, and the remaining open questions are highlighted. (shrink)

Despite 250 years of work in systematics, the majority of species remains to be identified. Rising extinction rates and the need for increased biological monitoring lend urgency to this task. DNA sequencing, with key sequences serving as a “barcode”, has therefore been proposed as a technology that might expedite species identification. In particular, the mitochondrial cytochrome c oxidase subunit 1 gene has been employed as a possible DNA marker for species and a number of studies in a variety of taxa (...) have accordingly been carried out to examine its efficacy. In general, these studies demonstrate that DNA barcoding resolves most species, although some taxa have proved intractable. In some studies, barcoding provided a means of highlighting potential cryptic, synonymous or extinct species as well as matching adults with immature specimens. Higher taxa, however, have not been resolved as accurately as species. Nonetheless, DNA barcoding appears to offer a means of identifying species and may become a standard tool. BioEssays 29: 188–197, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

This Christian sermon uses a DNA lab experience as a basis for theological reflection on ourselves and our offering. Who are we to God? What determines the self that we offer? Can the alphabet of DNA shed light for us on the Word of God in our lives? This first attempt to introduce the language and laboratory environment of genetic testing (represented by DNA fingerprinting) within a parish preaching context juxtaposes liturgical, scientific, and biblical language and settings for fresh insights.

Definition of the problem:The frequency and scope of human genetic banking has increased significantly in recent years and is set to expand still further. Two of the major growth areas in medical research, pharmacogenomics and population genetics, rely on large DNA banks to provide extensive, centralised and standardised genetic information as well as clinical and personal data. This development raises ethical concerns. Arguments and conclusion: Our article focuses on the appropriateness of informed consent as a means to safeguard both research (...) subjects’ rights and their good will. It will be argued that information requirements are extensive, with regard to non-therapeutic research, feedback, type of consent and possible breaches of confidentiality as well as possible implications for third parties. Given the demand of these requirements and the danger that research facilitated by these huge DNA banks may not reflect public priorities, it is argued that the research needs be steered by trustees to ensure that the altruistic act of sample donation contributes to the public good. (shrink)

During the past few years significant progress has been made in our understanding of the structure and function of the proteins involved in eukaryotic DNA replication. Data from several laboratories suggest that, in contrast to prokaryotic DNA replication, two distinct DNA polymerases are required for eukaryotic DNA replication, i.e. DNA polymerase delta for the synthesis of the leading strand and DNA polymerase alpha for the lagging strand. Several accessory proteins analogous to prokaryotic replication factors have been identified and some of (...) these are specific for pol delta whereas others affect both DNA replicases. The replicases and their accessory proteins appear to be highly conserved in eukaryotes, as homologous proteins have been found in species ranging from humans to yeast. (shrink)

In 1871, the Swiss physiological chemist Friedrich Miescher published the results of a detailed chemical analysis of pus cells, in which he showed that the nuclei of these cells contained a hitherto unknown phosphorus-rich chemical which he named ‘nuclein’ for its specific localisation. Published in German, ‘Ueber Die Chemische Zusammensetzung Der Eiterzellen’, [On the Chemical Composition of Pus Cells]Medicinisch-Chemische Untersuchungen(1871) 4: 441–60, was the first publication to describe DNA, and yet remains relatively obscure. We therefore undertook a translation of the (...) paper into English, which, together with the original article, can be accessed via the following linkhttps://doi.org/10.1017/S000708742000062X. In this paper, we offer some intellectual context for its publication and immediate reception. (shrink)