The prevalence of genetic markers in ETV disease patients in the 19th Health Department of Valencian Community were: FVL: 9.2%; PT20210 A: 10.5% and Ho-MTHFR: 23.7%. The FVL and PT20210 A prevalence results are lower respect to the literature, while Ho-MTHFR patients, have a higher prevalence with statistical significance difference respect the control group. We considered FVL, PT20210 A and Ho-MTHFR as ETV risk markers. The prevalence of genetic markers in healthy population of the same Health Department were: FVL: 5.8%; PT20210 A: 7.1%, and Ho-MTHFR: 7.7%. We must considered the specific study of these genetic risk markers (FVL, PT20210 A, Ho-MTHFR) in ETV disease affected subjects. The study of first degree relatives of the analyzed patients, should be of great utility to planified genetic advice and practice ETV prophylaxis.