RESUMEN
<p><b>OBJECTIVE</b>To study the prevalence of methylenetetrahydrofolate reductase (MTHFR) C677T genotype and its association with deep vei n thrombophilia in Chinese.</p><p><b>METHODS</b>Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was conducted to examine mutation with 63 deep vein thrombophilic patients and 80 health controls in Shandong Hans. The genotype frequencies were calculated by gene counting in patients and controls, and an analysis was made on the association of MTHFR C677T mutation with deep venous thrombosis in Shandong Hans.</p><p><b>RESULTS</b>In case- controls, the frequencies of C/T heterozygote were 41.27% and 43.75%; whereas those of T/T homozygote were 52.38% and 36.25%. Significantly elevated mutation was observed in patients(Chi-square=6.372, P 0.01 OR(T/T)=4.552 95% confidence interval:1.440-14.390, Chi-square =6.742 P=0.009).</p><p><b>CONCLUSION</b>The C677T mutation of methylenetetrahydrofolate reductase gene is a risk factor associated with deep vein thrombophilia in Shandong Hans.</p>