CHROMOSOMAL MOSAICISM, X CHROMOSOME ANOMALY AND SEX CHROMATIN DISCREPANCY IN A CASE OF GONADAL DYSGENESIS

Abstract

ABSTRACT The case of a 15-year-old phenotypic female with apparent traits of gonadal dysgenesis, horse shoe kidney and mentally retarded is presented. The sex chromatin was negative as judged from the polymorphonuclear leukocytes, none having been found with a drumstick. In the nuclei of the oral mucosa cells, however, Barr bodies were clearly distinguishable but were unusually small and few in number. Chromosome preparations made from cultures of leukocytes from the peripheral blood revealed a 45/46 mosaicism. The cells with 45 chromosomes apparently had only one X chromosome. In the other stemline, there was a supernumerary chromosome in the group 17–18, which was judged to be a deleted X The chromosomal aberration is thought to explain the discrepancy in the findings of sex chromatin. »Erosions« were frequently found in some of the chromosomes. Their significance is briefly discussed.