Derivative Y chromosome resulting from a t(Y;15) (q12; q11.2) in a boy with Prader-Willi syndrome

Chromosome analysis of peripheral lymphocytes from a boy with Prader-Willi syndrome showed the presence of 45 chromosomes, including der(Y) resulting from a t(Y;15) (q12; q11.2). In situ hybridization using DYZ3 and D15S11 showed a positive signal and negative signal in derivative Y chromosome, respectively. The deficiency of 15pter q11.2 may not influence the clinical manifestation of Prader-Willi syndrome.