Maternal UPD 20 in a hyperactive child with severe growth retardation.

摘要: Maternal uniparental disomy was observed in a 4-year-old boy with severe pre- and postnatal growth retardation (body height: 85 cm = 12 < third percentile, head circumference: 48 10 percentile), few minor facial findings, apparent hyperactivity. His intelligence is within the normal range for his age. Karyotype analysis revealed two cell lines, one apparently 46,XY, other tiny marker (47,XY, + mar). Microdissection reverse chromosome painting using DNA library as probe, well PCR that from 20 contains only centromere pericentromeric segments, but none of loci microsatellites. Microsatellite 25 disclosed maternal all 16 informative markers. heterodisomy evident seven short arm segment 20p11.2-pter. isodisomy found at five loci, three them map to proximal 20p11.2 20q. To our knowledge, this first case humans.