Translocations in Prader-Willi syndrome.

The Prader-Willi Syndrome (PWS) has frequently been associated with chromosomal anomalies involving the region 15q11-q12. The first case of this syndrome associated with a de novo translocation involving chromosomes 11 and 15 is reported. The breakpoints were identified as 11q25 and 15q11 or q12[45, XX,t(11;15)(q25;q11-12)], resulting in the deletion of 15pter leads to 15q11-q12. Previously reported cases of PWS associated with translocations are reviewed in relation to the "deletion hypothesis."