Translocation dicentric chromosomes in prostaglandin E2 induced abortuses and possible aneusomy through asynchronous centromeric divisions

Abstract

Translocations of a whole chromosome or a chromosome arm have been reported in both normal and abnormal liveborns. Often the abnormal phenotypes could not be explained by the genetic defects of the specific chromosome findings. Warburton et al. described an autosomal anomaly, tdic(12;14), showing gonadal dysgenesis; Pallister et al. described a patient with multiple congenital anomalies and mental retardation who had a normal karyotype in her fibroblasts. The whole chromosome translocation (6;19) was found in her lymphocytes only. Various genetic explanations have been proposed, including 'undetected' lesions, position effects, mutations at the sites of breakage and union, and aneusomy by recombination. Perhaps the whole chromosome translocation per se were not responsible for the malformations, since they were not necessarily found in cells of the deformed organs, or if they were, the abnomalities were not always explained by aberrations of the specific chromsomes involved in the translocations. We suggest another possibility, namely, that the developmental disturbances arise as epigenetic effects mediated by genetically imbalanced cells produced by the cells with the whole chromosome translocations.