Gonadoblastoma, mixed germ cell tumor, and Y chromosomal genotype: Molecular analysis in four patients

This study reports on Y chromosomal genotypes of three patients with gonado blastoma and one patient with gonadoblastoma and mixed germ cell tumor. Mol ecular analysis for 35 Y chromosomal loci was performed for DNA samples tak en from peripheral leukocytes and lymphoblastoid cell lines, showing that t he four patients shared the region between DYS267 at interval 4A and DYF50S 1 at interval 6D, with the exception of the region around DYS202 at interva l 5K. In the patient with gonadoblastoma and mixed germ cell tumor, Y chrom osomal material was preserved in the gonadoblastoma but was lost from the m ixed germ cell tumor. The results, in conjunction with previous reports, su ggest that GBY (gonadoblastoma locus on the Y chromosome) may be located to a roughly 5-Mb pericentromeric region between DYS267 at interval 4A and DY S270 at interval 5A. The presence of Y chromosomal material in gonadoblasto ma is consistent with GBY being involved in the development of gonadoblasto ma, and the absence of Y chromosomal material in mixed germ cell tumor woul d be explained as a consequence of Y chromosomal loss from rapidly prolifer ating gonadal cancer cells. Genes Chromosomes Cancer 25:40-45, 1999. (C) 19 99 Wiley-Liss, Inc.