Loss of heterozygosity on 6q, 16q, and 17p in human central nervous system primitive neuroectodermal tumors.

The loss of genetic material from specific chromosomal locations in a given tumor type has been taken for evidence of the importance of tumor suppressor genes at these loci in the genesis of the tumor. The primitive neuroectodermal tumor of the central nervous system has such a loss on 17p in one-third of tumors. In this report, a detailed analysis of 17p loss in 23 tumors has been performed using 10 probes mapping to this region. In addition, an analysis for allelic deletion on chromosomes 6q, 16q, and 22q has been performed. Six of the 23 tumors showed loss of markers on 17p, and the area of common loss spanned 17p11.2 to 17pter. Five of 23 tumors showed loss of markers on 6q, and 3 showed loss on 16q. No tumor lost markers on 22q. Only one tumor showed loss at more than one location. These data suggest that primitive neuroectodermal tumors either are a heterogeneous group of tumors with more than one mechanism leading to a tumor or that more than one recessive oncogene may play a role in the genesis of these tumors.