Hemihypotrophy in a girl with a translocation t(13q;7p).

A 10 year old girl with a mental age of 7-8 years, normal height and head circumference and several minor anomalies had hemiasymmetry of the entire body, the left side being uniformly smaller than the right. The smaller side was considered the abnormal side and her condition interpreted as hemihypotrophy on the basis of a chromosome abnormality which involved mosaicism, with lymphocytes showing a balanced but very unequal translocation of most of 13q transferred to 7p and both translocation chromosomes being present, and all examined fibroblasts lacking the small translocation chromosome and hence being monosomic for 13p, proximal part of 13q and a terminal portion of 7p.