Even as classic cytogenetics has given way to molecular karyotyping, and as new deletion and duplication syndromes are identified almost every day, the fundamental role of the genetics clinic remains mostly unchanged. Genetic counselors and medical geneticists explain the "unexplainable," helping families understand why abnormalities occur and whether they're likely to occur again. Chromosome Abnormalities and Genetic Counseling is the genetics professional's definitive guide to navigating both chromosome disorders and the clinical questions of the families they impact. Combining a primer on these disorders with the most current approach to their best clinical approaches, this classic text is more than just a reference; it is a guide to how to think about these disorders, even as our technical understanding of them continues to evolve. Completely updated and still infused with the warmth and voice that have made it essential reading for professionals across medical genetics, this edition of Chromosome Abnormalities and Genetic Counseling represents a leap forward in clinical understanding and communication. It is, as ever, essential reading for the field.

This new edition now titled “Human Chromosome Variation: Heteromorphism, Polymorphism and Pathogenesis” provides the reader with an up-to-date overview of microarrays, fragile sites, copy number variations and whole genome sequencing. Greatly expanding the discussion of microarray analysis in the previous edition of the book, are new chapters on microarray and genomic analysis, plus comprehensive tables on the subtle microdeletions and microduplications that are found on each chromosome, including 235 recurring copy number variants that are associated with well-established or emerging chromosomal syndromes. The current edition features concise information on cytogenetic methods and applications, extending these discussions to DNA analysis and genome sequencing. Sections on euchromatin, heterochromatin, FISH pattern, fragile site, copy number, and DNA sequence variation are integrated with actual clinical examples from cytogenetic laboratories and from clinical practice. The principles that allow for the distinction between benign chromosome / DNA variation and pathogenic heteromorphisms / polymorphisms are discussed and include references to the latest organizational guidelines and genomic or population databases. The two previous incarnations of this book: the ‘Atlas of Human Chromosome Heteromorphism’, and ‘Human Chromosome Variation: Heteromorphism and Polymorphism’ have been standard reference works in most cytogenetic laboratories, used by laboratory directors and clinicians all around the world. While widely used sections from the previous edition on cytogenetic technologies and heteromorphisms are retained intact the present volume adds extensive material on copy number variations (polymorphisms detected by microarray analysis), fragile sites in disease and cancer, and practical views on interpreting emerging technologies, including whole exome sequencing. This book should be of interest to clinicians, technicians and students who are or will be exposed to DNA and/or chromosome analysis and the data derived from these continuously developing techniques. This fully updated book volume will bring the reader up to speed on the latest technologies, their applications, benefits and drawbacks and as such, is a must read for anyone with an interest in DNA and chromosome analysis and the distinction between benign variation and pathogenic mistakes.

Advances in cytogenetics continue to crop up in wonderful ways, and we know exponentially more about chromosomes now than mere decades ago. Likewise, the necessary skills in offering genetic counseling continue to evolve. This new edition of Chromosome Abnormalities in Genetic Counseling offers a practical, up-to-date guide for the genetic counselor to marshal cytogenetic data and analysis clearly and effectively to families.

Human Chromosome Variation: Heteromorphism and Polymorphism was formerly printed under the title “Atlas of Human Chromosome Heteromorphism”. The Atlas has become a standard reference book in most cytogenetic laboratories and is cited as a significant reference in ISCN 2009. This revised version has updated and retained the most useful pictorial sections of the first edition, including the comprehensive review of normal and “not-so-normal” variations of the human karyotype with summaries and extensive reference lists organized by chromosome number. This updated edition features concise background information on chromosome methods and applications, essential information on heteromorphism frequencies in normal and clinical populations as well as new listing and discussions of euchromatic, subtelomeric and FISH variants. The addition of two new sections make this an even more valuable reference than before. A section on common and rare fragile sites includes a short historical discussion, definitions and an extensive table of officially recognized sites that includes the HUGO name, chromosomal location, methods of induction, genes and references to the most recent molecular characterization. A new section on array CGH discusses the clinical challenge of interpreting copy number variations (CNVs) revealed by this newest technology, gives examples of various levels of interpretation and lists the several most common websites used in this interpretation.

Critical to the accurate diagnosis of human illness is the need to distinguish clinical features that fall within the normal range from those that do not. That distinction is often challenging and not infrequently requires considerable experience at the bedside. It is not surprising that accurate cytogenetic diagnosis is also often a challenge, especially when chromosome study reveals morphologic findings that raise the question of normality. Given the realization that modern human cytogenetics is just over five decades old, it is noteworthy that thorough documentation of normal chromosome var- tion has not yet been accomplished. One key diagnostic consequence of the inability to distinguish a “normal” variation in chromosome structure from a pathologic change is a missed or inaccurate diagnosis. Clinical cytogeneticists have not, however, been idle. Rather, progressive biotechnological advances coupled with virtual completion of the human genome project have yielded increasingly better microscopic resolution of chromosome structure. Witness the progress from the early short condensed chromosomes to the later visualization of chromosomes through banding techniques, hi- resolution analysis in prophase, and more recently to analysis by fluorescent in situ hybridization (FISH).

The fourth edition of this well-known text provides students, researchers and technicians in the area of medicine, genetics and cell biology with a concise, understandable introduction to the structure and behavior of human chromosomes. This new edition continues to cover both basic and up-to-date material on normal and defective chromosomes, yet is particularly strengthened by the complete revision of the material on the molecular genetics of chromosomes and chromosomal defects. The mapping and molecular analysis of chromosomes is one of the most exciting and active areas of modern biomedical research, and this book will be invaluable to scientists, students, technicians and physicians with an interest in the function and dysfunction of chromosomes.