Abstract 813 Poster Session IV, Tuesday, 5/4 (poster 209)

The polymorphic mutation C677T in the gene of MTHFR is considered a risk mutation for spina bifida and vascular disease. Another common mutation on the MTHFR gene, A1298C has also been described which is also considered a risk mutation. We studied the frequencies of these two mutations on DNA samples from healthy Jewish individuals and compared them to the frequency of these mutations in DNA samples obtained from healthy individuals in South Texas. The presence C677T allele was determined by PCR and HinfI digestion, and mutation A1298C by PCR and MboII digestion. Total of 310 alleles were examined for C677T in the Ashkenazi samples and 400 alleles in the non Jewish samples. The rate of C677T among the Jewish alleles was 47.7% as compared to 28.7% among the alleles from the non Jewish individuals. The difference is statistically significant p=0.0005. Mutation A1298C was examined in 298 alleles of Jewish individuals and 374 alleles of non Jewish counterparts. The rate of the A1298C mutation in the Jewish samples was 27.2% while in the non Jewish was 35.0%. The p=0.031 which is also significant. No individuals were homozygous for both mutations and no individuals were found to be homozygous to one mutation with heterozygosity of the other mutation. Our study shows that the C677T and the A1298C alleles never occurred in cis position in the studied samples. Our study shows a very high frequency of the C677T allele among the Ashkenazi Jews while the A1298C has a lower frequency in this population. These findings are of interest because spina bifida is less common among Ashkenazi Jews. Further studies are needed to establish whether the C677T and the A1298C mutations have impact on vascular disease in the Ashkenazi Jewish population.