Asymmetrical, reciprocal translocation (45,XX,tdic(9;17) (p21;p12).

A nine-month-old girl with dysmorphic features, congenital heart disease and chromosomal mosaicism is reported. Approximately one-half of the cells (lymphocytes and fibroblasts) showed a normal karyotype 46, XX, the other half a dicentric translocation chromosome. Using the G-band technique, the dicentric chromosome was identified as a 9/17 translocation chromosome. Both centromeres of the translocation chromosome could be stained to the same degree, using the C-band technique. The centromere region of chromosome No. 9 was in addition demonstrated, by using the Giemsa 11 technique.