Cell line segregation in a 45,X/46,XY mosaic child with asymmetric leg growth.
Clinical evaluation of a 13 1/2-year-old male revealed a 4.4-cm leg length discrepancy and a small penis with a normal endocrine evaluation. Cytogenetic analysis of peripheral blood lymphocytes and skin fibroblasts derived from the back showed 45,X/46,XY mosaicism with similar percentages of 45,X cells, 36% and 30% respectively. However, two separate skin fibroblast cultures derived from the thigh and calf of the short (right) leg showed significant lack of Y-bearing cells with 100% and 80% 45,X, respectively. In contrast, skin biopsies of the thigh and calf of the normal (left) leg both showed 100% 46,XY. Similar evidence for differences in the percentages of Y-bearing cells in the left versus right leg fibroblast cultures was obtained using densitometric scanning of dot blots following DNA hybridization with a Y-specific probe at the DYZ4 locus. Asymmetric limb growth in cases of X/XY lymphocyte mosaicism warrants further cytogenetic investigation to substantiate possible genotype-phenotype correlations which may help uncover the fundamental growth deficiency in Turner syndrome.
Papenhausen
P R
PR
Department of Pediatrics, University of South Florida, College of Medicine, Tampa.
Mueller
O T
OT
Bercu
B
B
Salazar
J
J
Tedesco
T A
TA
D000293:Adolescent; D002460:Cell Line; D002871:Chromosome Banding; D004247:DNA / Q000235:genetics; D006801:Humans; D007870:Leg Length Inequality / Q000235:genetics*; D008297:Male; D008540:Meiosis / Q000235:genetics; D009030:Mosaicism / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D010413:Penis / Q000002:abnormalities; D012729:Sex Chromosome Aberrations; D014960:X Chromosome; D014998:Y Chromosome
D004247:DNA