Prevalence of factor V Leiden and prothrombin G20210A gene mutation.

OBJECTIVES: To determine the prevalence of factor V Leiden (FVL) and prothrombin gene (PG) 20210A mutations in patients who attended the outpatient clinic and do not have a family history of thrombosis.

METHODS: We researched FVL and PG20210A mutations in 151 outpatients (92 males and 59 females) who attended the Pediatrics Polyclinic, Medical Faculty, Dicle University, Turkey between May 2002 and July 2002. Peripheral venous bloods (2 cc) with ethylenediaminetetraacetic acid were used to isolate DNA by high pure polymerase chain reaction (PCR). Later, by using light-cycler FVL (Roche) and prothrombin mutation detection kit (Roche) and light-cycler equipment, FVL and PG20210A gene mutations were determined from the samples in the glass capillary tubes by PCR specific adaptation. For active protein C (APC) resistance, STA-STACLOT APC-R Detection Kit was used. Expected values were evaluated with STA equipment and using STA-STACLOT APC-R procedure.

RESULTS: The prevalence of heterozygote mutations of FVL was 4.6% and PG20210A was 0.7%. The FVL mutation frequency obtained in our study is lower than the other studies in Turkey, but in correlation with the results of the other Caucasian populations throughout the world. Active protein C resistance in patients carrying heterozygote mutation of FVL has been found in low rates. Factor V Leiden and PG20210A were confronted in high prevalences in patients who suffer venous thrombosis (VT) CONCLUSION: Scanning of FVL and PG20210A gene mutations may be recommended in high risk groups such as relatives of FVL and PG20210A carriers and relatives of patients with VT, and in during pregnancy, the use of oral contraceptives and before surgery. Routine scanning of FVL and PG20210A gene mutations is not recommended in people who do not have risk factors for VT.