A homologous tandem translocation [45,XX,-13,-13,+t(13;13) (q12;q34)]

Chromosomal investigation of a young girl with mental and motor retardation and congenital anomalies revealed a translocation between both members of pair No. 13. Banding analysis showed that the translocation was "tandem," leading to monosomy for segments in both the long and short arms of No. 13.