Skin pigment anomalies and mosaicism for a double autosomal trisomy (48,XX,+18,+20).
We present a patient with profound mental retardation, epilepsy, facial dysmorphism and multiple skin hyper- and depigmentation areas. Karyotype in white blood cells was normal female, whereas in cultured skin fibroblasts originating from a depigmentated area, mosaic 48,XX,+18,+20 was found. Molecular analyses using polymorphic microsatellites showed a different origin of both additional chromosomes: maternal for the chromosome 20, paternal for chromosome 18. This, together with a mosaic state is consistent with a double postzygotic error in chromosome segregation possibly occurring in a single cell division.
Devriendt
K
K
Center for Human Genetics, University of Leuven, Belgium.
Matthijs
G
G
Meireleire
J
J
Roelen
L
L
van Buggenhout
G
G
Fryns
J P
JP
D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000235:genetics; D000328:Adult; D000782:Aneuploidy; D002869:Chromosome Aberrations / Q000235:genetics*; D025063:Chromosome Disorders; D002887:Chromosomes, Human, Pair 18; D002890:Chromosomes, Human, Pair 20; D005260:Female; D006801:Humans; D009030:Mosaicism; D010859:Pigmentation Disorders / Q000175:diagnosis / Q000235:genetics*; D014314:Trisomy