Familial transmission of a translocation between two chromosomes of the 13–15 group (Denver classification)

Abstract

Summary A family has been described in which the transmission of a translocation between two chromosomes of the 13–15 group can be traced through at least three generations. All balanced translocation carriers are apparently normal. A close approximation of a 1:1 ratio of carriers: normal has been found in the offspring from such translocation carriers, and this is compared with published data for the transmission of a 15/21 translocation associated with Down's syndrome. There is no conclusive evidence for the occurrence of trisomy in the family. The data suggest the absence of close linkage between the translocation and the ABO, Rhesus, MNS, ‘P’ and Duffy blood‐group loci.