Triplication of distal chromosome 10q

We describe a patient with a de novo chromosomal aberration with karyotype 46,XY,10q+, presenting clinical features of partial duplication of distal c hromosome 10q. Further studies using microsatellites and FISH showed a trip lication of distal chromosome 10q. The rearrangement involved both maternal homologues and the middle chromosomal 10q fragment of the triplication was inverted, similar to previously reported chromosomal triplications. Chromo somal triplications may be more frequent than assumed and may share a commo n molecular mechanism.