Familial pericentric inversion of chromosome 19, inv(19) (p13q13) with a note on genetic counseling of pericentric inversion carriers

Abstract

An inmate of a hospital for the mentally retarded was found during a cytogenetic screening programme to have karyotype 46,XY,inv(19)(p13q13)mat. Clinical, cytogenetic and family findings are presented and it is concluded that the chromosomes abnormality was probably not the cause of the patient's retardation. The problem of genetic counseling of inversion carriers is examined in some detail and estimates of risk are given.

PIP: Familial pericentric inversion of chromosome 19,inv(19)(p13q13) and genetic counseling of pericentric inversion carriers are discussed. During a cytogenic screening program a patient of a hospital for the mentally retarded was found to have karyotype 46,XY,inv(19)(p13q13)mat. The presence of an identical inversion chromosome in the mother and both normal siblings of the propositus was seen. Following analysis of cytogenetic, clinical, and family findings, it is concluded that the chromosome abnormality was probably not the cause of the patient's retardation. Genetic counseling of inversion is examined in detail and estimates of risks are presented.