title: Paternal non-disjunction in a 46,XY/47,XXY individual with a fragile 17p12 in the mother.
abstract: In a family where the mother carried a fragile site at 17p12, RFLP-analysis with the X-specific probe L1.28 showed that the 46,XY/47,XXY mosaicism detected in her Klinefelter son was due to a non-disjunctional event in paternal meiosis I, followed by a secondary loss of an X-chromosome by a mitotic non-disjunction. Thus, an association between the primary meiotic non-disjunction and the presence of the fragile site could be excluded.
mesh_terms: D000293:Adolescent; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D002886:Chromosomes, Human, Pair 17; D005260:Female; D006801:Humans; D007713:Klinefelter Syndrome / Q000235:genetics*; D008297:Male; D008540:Meiosis; D009030:Mosaicism; D012150:Polymorphism, Restriction Fragment Length