CHROMOSOME 12-CONTAINING MARKERS, INCLUDING 2 DICENTRICS, IN 3 I(12P)-NEGATIVE TESTICULAR GERM-CELL TUMORS

A chromosome 12-derived marker was seen in each of 3 testicular germ cell tumors that lacked the i(12p). An interesting feature of 2 of the markers was that the major part, including the centromere, of an acrocentric (a #13 and #14, respectively) was translocated onto 12p, resulting in a dicentric. In the third tumor, 13q (translocated onto 12q) was again probably involved in the rearrangement. The findings support the view that the amplification of genes on 12p represents a significant step in the development of germ cell tumors.