Vijay S. Tonk – författare

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).

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).

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).

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. Thisbook 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.

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. 

Thisbook 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.