The allele frequency of mutations in four genes that confer enhanced susceptibility to venous thromboembolism in an unselected group of New York State newborns.

The frequencies of Factor V G1691A (FVL), prothrombin (PT) G20210A, 5'10'methylenetetrahydrofolate reductase (MTHFR) C677T, and methionine synthase (MS) A2756G (four mutations associated with an increased risk of venous thromboembolism [VTE]) were determined in a sample of approximately 1500 New York State residents. Dried blood spots from approximately equal numbers of Caucasians, African-Americans and Hispanics were anonymously obtained from the New York State Department of Health Newborn Screening Program. Following PCR amplification of dried blood spot DNA, allele-specific oligonucleotide hybridization was used to detect mutant alleles. The total number of individuals at increased genetic risk for VTE was 271 (17.5%) of the 1553 persons tested. Increased genetic risk was defined as the heterozygous state for FVL or PT and the homozygous state for the MTHFR or MS polymorphisms. Sixteen individuals had more than one genetic risk factor. The MS gene variant allele frequencies for African-Americans and Hispanics are the first to be reported. This report also provides an estimate of the variant PT allele in the largest group of Hispanics studied to date.