Abstract for presentation at 11th International Congress of Human Genetics

Gliomas are the most common brain tumors, comprising nearly half of all primary brain tumors, and in Finland they are among the top-ten list of common cancer types. The etiology of gliomas is poorly understood. We have performed a genome-wide linkage study in 19 familial glioma families from Finland. The strongest evidence of genetic effect was found on 15q26.1 with a NPL score of 3.4 (Paunu et al. Cancer Res 62:3798, 2002). Fine-mapping was focused on two regions within the broad linkage area, association region at the telomere to 15q and the centre linkage peak. We could not find significant allele associations with additional 8 microsatellite markers near the telomere. In the centre peak region, with 17 more SNPs the original peak has been narrowed down to ~12.5 cM with a maximum NPL score of 3.35. Furthermore, we have also performed a high-dense SNP association screening using the Affymetrix GeneChip Human Mapping 10K Array in five patients from four pedigrees showing linkage, which allowed us to pinpoint potentially identically-by-descent shared regions and candidate genes for sequencing analysis. One variant from one of four sequenced genes has been mapped to the centre region and showed strong linkage together with adjacent SNPs. However, more intensive investigation on candidate genes and their function is needed to determine if this region indeed forms a susceptibility locus for inherited brain tumors.