The OGG1 gene, which codes for a DNA repair protein with antimutator activi
ty, Is located on chromosome 3p25, a frequent site of allelic deletions in
many types of human tumors, including renal clear cell cancers, We present
the analysis of 99 renal tumors for alterations in the OGG1 gene to determi
ne its association with tumorigenesis, Loss of heterozygosity in the 3p25 r
egion was found for 85% of the informative cases, We detected somatic misse
nse mutations of the OGG1 gene in 4 of the 99 tumor samples. Biochemical an
alysis of the mutant proteins revealed that a substitution at codon 46 impa
irs the enzymatic activity. We also describe the occurrence of several poly
morphisms as well as aberrantly spliced OGG1 transcripts.