Pure trisomy 10p involving an isochromosome 10p

We report a child with trisomy 10p due to a translocation of the long arm o f chromosome 10 to the short arm of chromosome 14 and isochromosome formati on of 10p [46,XX,i(10)(p10),der(14)t(10;1 4)(q10;p10)]. Most reported cases of trisom y 10p involve double segmental imbalance. In contrast, the clinical feature s described in the current case represent pure trisomy 10p and, thus. delin eate the 10p trisomy syndrome phenotype. Mechanisms of the chromosomal rear rangements in this case are suggested.