hRAD54 gene and 1p high-resolution deletion-mapping analyses in oligodendrogliomas

The hRAD54 protein belongs to a superfamily of DNA helicases, and mutations in genes with DNA helicase function have been found to be responsible for cancer-prone syndromes (xeroderma pigmentosum, Bloom syndrome, Werner syndr ome). hRAD54 thus could be a candidate modifier gene in tumors characterize d by allelic imbalance at 1p32, the chromosome region in which this gene is located. Using a panel of 38 1p and five 1q markers, we therefore performe d deletion-mapping analysis on a series of 35 oligodendrogliomas, which wer e also studied for mutations in the hRAD54 gene. Deletions of the short arm of chromosome 1 were evidenced in 26 tumors, mostly involving 1p36-1p13; a ll thus displayed loss of the 1p32 region. We used PCR/SSCP to examine all 18 exons of the hRAD54 gene for mutations in 25 tumors, but the mobility sh ifts detected corresponded to previously identified polymorphic changes: T- to-C transition at nucleotide 2865 (with no amino acid change) and at nucle otide 3008, at the 3' untranslated region. We conclude that hRAD54 gene alt erations are not required for malignant transformation of oligodendroglioma s. (C) Elsevier Science, Inc., 1999. All Rights Reserved.