Chromosome Abnormalities and Genetic Counseling

Chromosome abnormalities have been known for over 50 years, though the methods of analysis have become increasing more sophisticated and precise. Surprisingly, the questions that parents and families raise in genetic counseling have changed little over that period. Questions like, "Why did an abnormality happen? Why did it cause the problems we see in our child? Would it happen again in a future child? How could we avoid it happening again?" are common concerns for families. This new edition of Chromosome Abnormalities and Genetic Counseling deals with these universal questions, and in the context of the recent developments in molecular cytogenetic analysis, but retaining always the major focus on the needs of the families in which these conditions occur. Thoroughly updated once again, this richly-illustrated text combines basic concepts of chromosomal analysis with practical applications of recent advances in molecular cytogentics. The book will give counselors the information that will enable them to help concerned parents accommodate and adapt to their particular chromosomal challenges and to determine what may be, for them, the best course of action.
Contents

Contents BASIC CONCEPTS 1. Elements of medical cytogenetics 2. Chromosome analysis: classical and modern methodologies 3. The origins and consequences of chromosomal pathology 4. Deriving and using a risk figure PARENT WITH A CHROMOSOMAL ABNORMALITY 5. Autosomal reciprocal translocations 6. Sex chromosome translocations 7. Robertsonian translocations 8. Centromere Fissions, Complementary Isochromosomes, Telomeric Fusions, Balancing Supernumerary Chromosomes, and Jumping Translocations 9. Inversions 10. Insertions 11. Autosomal ring chromosomes 12. Complex rearrangements 13. Parental sex chromosome aneuploidy 14. Parental autosomal aneuploidy 15. The fragile X syndromes VARIANTS 16. Variant chromosomes and abnormalities of no phenotypic consequence 17. Copy number variants NORMAL PARENT WITH A CHROMOSOMALLY ABNORMAL CHILD 18. Down syndrome, other full aneuploidies, and polyploidy 19. Structural rearrangements 20. Chromosomal disorders of sex development 21. Chromosome instability syndromes DISORDERS ASSOCIATED WITH ABERRANT GENOMIC IMPRINTING 22. Uniparental disomy and disorders of imprinting REPRODUCTIVE FAILURE 23. Gametogenesis and conception, pregnancy loss, and infertility PRENATAL DIAGNOSIS 24. Parental age counseling and screening for fetal trisomy 25. Prenatal diagnostic procedures 26. Preimplantation genetic diagnosis 27. Chromosome abnormalities detected at prenatal diagnosis NOXIOUS AGENTS 28. Gonadal cytogenetic damage from exposure to extrinsic agents APPENDICES A. Ideograms of human chromosomes and haploid autosomal lengths B. Cytogenetic abbreviations and nomenclature C. Determining 95 per cent confidence limits and the standard error References Index