DNA samples from 26 cervical carcinoma and normal tissue pairs were studied by restriction fragment length polymorphism (RFLP) analysis to determine the frequency of loss of heterozygosity (LOH) on 17p. Allelic loss in the p13.1 region of chromosome 17, known to contain the TP53 locus, was not detected in any of 10 informative cases. Instead, LOH was detected on 17p13.3 in eight (40%) of 20 informative cases with at least one of two 17p13.3 markers. Examination of the intragenic region of p53 in the same samples using polymerase chain reaction (PCR)-RFLP analysis showed no LOH in the gene (none of 16 informative individuals).