title: Additional pedigree supporting the frequent origin of XXYY from consecutive meiotic non-disjunction in paternal gametogenesis.
abstract: A 48,XXYY Sardinian patient, born to a 46,XX mother heterozygous for the Gd Mediterranean mutant, and to a 46,XY father hemizygous for the same mutant, was found to have a mosaic distribution of G6PD(+) and G6PD(-) peripheral red blood cells. The most likely interpretation of this finding is that the propositus is an additional example of an XXYY zygote derived from a consecutive meiotic non-disjunction during paternal gametogenesis.
mesh_terms: D000328:Adult; D005260:Female; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D007558:Italy; D008297:Male; D008540:Meiosis; D009030:Mosaicism; D010375:Pedigree; D012729:Sex Chromosome Aberrations / Q000235:genetics*