B Chromosomes In The Eukaryote Genome

B chromosomes are additional passengers found in the karyotypes of about 15% of eukaryote species. They are best understood as genome parasites exploiting the host genome because of their transmissional advantage, and are frequently deleterious for the organism carrying them. Since the last compilation of B chromosome literature more than 20 years ago, many new findings have contributed to building an increasing body of knowledge of these mysterious genetic elements. This single topic issue of Cytogenetic and Genome Research updates these new data in its 40 papers authored by researchers from 19 countries. It provides up-to-date reviews on plants, fish, amphibians and mammals and, for the first time, on Sternorrhyncha hemipterans, decapodan crustaceans, helminth parasites and lizards. It also presents new original data on many aspects of B chromosomes including their definition, new occurrences, frequency, structure, composition, origin, effects on the host genome, transmission and population dynamics. Unique in its field, this publication is recommended reading for cytogeneticists interested in chromosome polymorphisms, for evolutionary biologists interested in selfish genetic elements, and for geneticists interested in the intragenomic conflict.

Supernumerary B chromosomes (Bs) are dispensable genetic elements found in thousands of species of plants and animals, and some fungi. Since their discovery more than a century ago, they have been a source of puzzlement, as they only occur in some members of a population and are absent from others. When they do occur, they are often harmful, and in the absence of “selfishness”, based on mechanisms of mitotic and meiotic drive, there appears to be no obvious reason for their existence. Cytogeneticists have long wrestled with questions about the biological existence of these enigmatic elements, including their lack of any adaptive properties, apparent absence of functional genes, their origin, sequence organization, and co-evolution as nuclear parasites. Emerging new technologies are now enabling researchers to step up a gear, to look enthusiastically beyond the previous limits of the horizon, and to uncover the secrets of these “silent” chromosomes. This book provides a comprehensive guide to theoretical advancements in the field of B chromosome research in both animal and plant systems.

This open access book offers the first comprehensive account of the pan-genome concept and its manifold implications. The realization that the genetic repertoire of a biological species always encompasses more than the genome of each individual is one of the earliest examples of big data in biology that opened biology to the unbounded. The study of genetic variation observed within a species challenges existing views and has profound consequences for our understanding of the fundamental mechanisms underpinning bacterial biology and evolution. The underlying rationale extends well beyond the initial prokaryotic focus to all kingdoms of life and evolves into similar concepts for metagenomes, phenomes and epigenomes. The book’s respective chapters address a range of topics, from the serendipitous emergence of the pan-genome concept and its impacts on the fields of microbiology, vaccinology and antimicrobial resistance, to the study of microbial communities, bioinformatic applications and mathematical models that tie in with complex systems and economic theory. Given its scope, the book will appeal to a broad readership interested in population dynamics, evolutionary biology and genomics.

There is growing enthusiasm in the scientific community about the prospect of mapping and sequencing the human genome, a monumental project that will have far-reaching consequences for medicine, biology, technology, and other fields. But how will such an effort be organized and funded? How will we develop the new technologies that are needed? What new legal, social, and ethical questions will be raised? Mapping and Sequencing the Human Genome is a blueprint for this proposed project. The authors offer a highly readable explanation of the technical aspects of genetic mapping and sequencing, and they recommend specific interim and long-range research goals, organizational strategies, and funding levels. They also outline some of the legal and social questions that might arise and urge their early consideration by policymakers.

This book celebrates the dawn of the rye genomics era with concise, comprehensive, and accessible reviews on the current state of rye genomic research, written by experts in the field for students, researchers and growers. To most, rye is the key ingredient in a flavoursome bread or their favourite American whisky. To a farmer, rye is the remarkable grain that tolerates the harshest winters and the most unforgiving soils, befitting its legacy as the life-giving seed that fed the ancient civilisations of northern Eurasia. Since the mid-1900s, scientists have employed genetic approaches to better understand and utilize rye, but only since the technological advances of the mid-2010s has the possibility of addressing questions using rye genome assemblies become a reality. Alongside the secret of its unique survival abilities, rye genomics has accelerated research on a host of intriguing topics such as the complex history of rye’s domestication by humans, the nature of genes that switch fertility on and off, the function and origin of accessory chromosomes, and the evolution of selfish DNA.

This reference book provides information on plant cytogenetics for students, instructors, and researchers. Topics covered by international experts include classical cytogenetics of plant genomes; plant chromosome structure; functional, molecular cytology; and genome dynamics. In addition, chapters are included on several methods in plant cytogenetics, informatics, and even laboratory exercises for aspiring or practiced instructors. The book provides a unique combination of historical and modern subject matter, revealing the central role of plant cytogenetics in plant genetics and genomics as currently practiced. This breadth of coverage, together with the inclusion of methods and instruction, is intended to convey a deep and useful appreciation for plant cytogenetics. We hope it will inform and inspire students, researchers, and teachers to continue to employ plant cytogenetics to address fundamental questions about the cytology of plant chromosomes and genomes for years to come. Hank W. Bass is a Professor in the Department of Biological Science at Florida State University. James A. Birchler is a Professor in the Division of Biological Sciences at the University of Missouri.

Concepts of Biology is designed for the single-semester introduction to biology course for non-science majors, which for many students is their only college-level science course. As such, this course represents an important opportunity for students to develop the necessary knowledge, tools, and skills to make informed decisions as they continue with their lives. Rather than being mired down with facts and vocabulary, the typical non-science major student needs information presented in a way that is easy to read and understand. Even more importantly, the content should be meaningful. Students do much better when they understand why biology is relevant to their everyday lives. For these reasons, Concepts of Biology is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand.We also strive to show the interconnectedness of topics within this extremely broad discipline. In order to meet the needs of today's instructors and students, we maintain the overall organization and coverage found in most syllabi for this course. A strength of Concepts of Biology is that instructors can customize the book, adapting it to the approach that works best in their classroom. Concepts of Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand--and apply--key concepts.