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.

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.

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.