Uniparental disomy resulting from heterozygous Robertsonian translocation (13ql4q) in both parents

Uniparental disomy (UPD) is a situation in which both members of a chromosome pair are inherited from one parent. This study has been conducted on a family with a five year-old healthy girl and a mentally retarded boy. The parents were first cousins and they both had Robertsonian translocation between their long arm of chromosome 13 and 14 [45, XY t (13ql4q)]. Their affected son had a similar karyotype. Their daughter s karyotype revealed the presence of a homozygous Robertsonian 13/14 translocation 44, XX t (13ql4), t(13ql4q). According to the clinical findings it is possible to conclude that the affected boy suffers from UPD.