Thomas Liehr – författare

Benign & Pathological Chromosomal Imbalances systematically clarifies the disease implications of cytogenetically visible copy number variants (CG-CNV) using cytogenetic assessment of heterochromatic or euchromatic DNA variants. While variants of several megabasepair can be present in the human genome without clinical consequence, visually distinguishing these benign areas from disease implications does not always occur to practitioners accustomed to costly molecular profiling methods such as FISH, aCGH, and NGS.

As technology-driven approaches like FISH and aCGH have yet to achieve the promise of universal coverage or cost efficacy to sample investigated, deep chromosome analysis and molecular cytogenetics remains relevant for technology translation, study design, and therapeutic assessment.

Knowledge of the rare but recurrent rearrangements unfamiliar to practitioners saves time and money for molecular cytogeneticists and genetics counselors, helping to distinguish benign from harmful CG-CNV. It also supports them in deciding which molecular cytogenetics tools to deploy.

Cytogenomics demonstrates that chromosomes are crucial in understanding the human genome and that new high-throughput approaches are central to advancing cytogenetics in the 21st century. After an introduction to (molecular) cytogenetics, being the basic of all cytogenomic research, this book highlights the strengths and newfound advantages of cytogenomic research methods and technologies, enabling researchers to jump-start their own projects and more effectively gather and interpret chromosomal data. Methods discussed include banding and molecular cytogenetics, molecular combing, molecular karyotyping, next-generation sequencing, epigenetic study approaches, optical mapping/karyomapping, and CRISPR-cas9 applications for cytogenomics. The book's second half demonstrates recent applications of cytogenomic techniques, such as characterizing 3D chromosome structure across different tissue types and insights into multilayer organization of chromosomes, role of repetitive elements and noncoding RNAs in human genome, studies in topologically associated domains, interchromosomal interactions, and chromoanagenesis.

This book is an important reference source for researchers, students, basic and translational scientists, and clinicians in the areas of human genetics, genomics, reproductive medicine, gynecology, obstetrics, internal medicine, oncology, bioinformatics, medical genetics, and prenatal testing, as well as genetic counselors, clinical laboratory geneticists, bioethicists, and fertility specialists.

Genomic technologies provide the means of diagnosis and management of many human diseases. Without insights from cytogenetics, correct interpretation of modern high-throughput results is difficult, if not impossible. This book summarizes applications of cytogenetics and molecular cytogenetics for students, clinicians and researchers in genetics, genomics and diagnostics. The book combines the state-of-the-art knowledge and practical expertise from leading researchers and clinicians and provides a comprehensive overview of current medical and research applications of many of these technologies.

KEY FEATURES

• Provides clear summaries of fluorescence in situ hybridization technologies and others

• Comprehensively covers established and emerging methods

• Chapters from an international team of leading researchers

• Useful for students, researchers and clinicians

Genomic technologies provide the means of diagnosis and management of many human diseases. Without insights from cytogenetics, correct interpretation of modern high-throughput results is difficult, if not impossible. This book summarizes applications of cytogenetics and molecular cytogenetics for students, clinicians and researchers in genetics, genomics and diagnostics. The book combines the state-of-the-art knowledge and practical expertise from leading researchers and clinicians and provides a comprehensive overview of current medical and research applications of many of these technologies.

KEY FEATURES

• Provides clear summaries of fluorescence in situ hybridization technologies and others

• Comprehensively covers established and emerging methods

• Chapters from an international team of leading researchers

• Useful for students, researchers and clinicians

This book presents chromosome-wise clinical cases following an evidence-based protocol, in addition to providing the scientific background on the mechanisms of human ring chromosome (RC) formation. Presence of RCs in a genome can lead to several rare genetic diseases. This book, edited by the leading experts Prof. Peining Li and Prof. Thomas Liehr, is the first comprehensive book on this topic.

Over the past 60 years, banding cytogenetics, fluorescence in situ hybridization, chromosome microarray analysis, and whole genome sequencing have been used to diagnose cases with a RC. Ring syndrome of sever growth retardation and variable intellectual disability has been considered a common clinical feature for all RCs. Clinical heterogeneity of chromosome-specific deletion and duplication syndromes, gene-related organ and tissue defects, cancer predisposition to different types of tumors, and reproduction failure has been reported in the literature. However, the cases of RCs reportedin the literature account for less than 1% of its real occurrence. Current diagnostic practice lacks laboratory standards for analyzing cellular behavior and genomic imbalances of RCs to evaluate its compound effects on patients. The under-representation of clinical cases and the lack of comprehensive diagnostic analysis make challenging to establish accurate clinico-cytogenomic correlations. Given recent advances in genomic technology and organized efforts from peer experts, standardized cytogenomic diagnosis and evidence-based clinical management could be envisioned for all patients with RCs.

Furthermore, supernumerary small ring chromosomes and the patient’s perspective are addressed—the latter by including family stories of RC-carrier relatives. Acquired RCs in various cancers are also discussed, as well as the potential role of RCs in research applications like iPSC cellular modeling and genomic editing.

This book is a valuable reference for clinical geneticists, personnel in cytogenetics and molecular genetics laboratories, genetic counselors, and researchers in related fields.

Human beings normally have a total of 46 chromosomes, with each chromosome present twice, apart from the X and Y chromosomes in males. Some three million people worldwide, however, have 47 chromosomes: they have a small supernumerary marker chromosome (sSMC) in addition to the 46 normal ones. This sSMC can originate from any one of the 24 human chromosomes and can have different shapes. Approximately one third of sSMC carriers show clinical symptoms, while the remaining two thirds manifest no phenotypic effects.

This guide represents the first book ever published on this topic. It presents the latest research results on sSMC and current knowledge about the genotype-phenotype correlation. The focus is on genetic diagnostics as well as on prenatal and fertility-related genetic counseling. A unique feature is that research meets practice: numerous patient reports complement the clinical aspects and depict the experiences of families living with a family member with an sSMC.

This book focus on genetic diagnostics for Uniparental Disomy (UPD), a chromosomal disorder defined by the exceptional presence of a chromosome pair derived from only one parent, which leads to a group of rare diseases in humans. First the molecular and cytogenetic background of UPD is described in detail; subsequently, all available information of the various chromosomal origins and the latest findings on genotype-phenotype correlations and clinical consequences are discussed.

Numerous personal reports from families with a child suffering from a UPD-induced syndrome serve to complement the scientific and clinical aspects. Their experiences with genetic counseling and living with a family member affected by this chromosomal aberration present a vivid picture of what UPD means for its victims.

This manual offers detailed protocols for fluorescence in situ hybridization (FISH) and comparative genomic hybridization approaches, which have been successfully used to study various aspects of genomic behavior and alterations. Methods using different probe and cell types, tissues and organisms, such as mammalians, fish, amphibians (including lampbrush-chromosomes), insects, plants and microorganisms are described in 57 chapters. In addition to multicolor FISH procedures and special applications such as the characterization of marker chromosomes, breakpoints, cryptic aberrations, nuclear architectures and epigenetic changes, as well as comparative genomic hybridization studies, this 2nd edition describes how FISH can be combined with other techniques. The latter include immunostaining, electron microscopy, single cell electrophoresis and microdissection.