PO629-MON Prevalence of VKORC-1 polymorphisms across caucasians and amerindians

VERA MORANDINI M; REMOTTI L; GROSSO SH; INGRATTI M; ALBERTO MF; CARUSO V; SÁNCHEZ LUCEROS A; MESCHENGIESER SS; LAZZARI MA; BLANCO A

Toronto

Congreso; XXV Congress of the International Society on Thrombosis and Haemostasis and 61st Annual SSC Meeting.; 2015

International Society on Thrombosis and Haemostasis

Background: Vitamin K epoxide reductase complex 1 (VKORC-1) is the target enzyme of vitamin K antagonists. Polymorphisms (SNPs) in VKORC-1 gene, mainly 1173C>T and 1639G>A, are associated with different sensitivity to oral anticoagulants (OA). The knowledge about the frequency of these SNPs in Amerindians is limited.Aims: The aim of the study was to determine, VKORC-1 SNPs (1173C>T and 1639G>A) frequency across Caucasians and descendants of Amerindians, in order to see possible differences between them.Methods: Subjects: 130 random patients were selected (40% males and 60% females with mean age of 62 (range: 8?95) year-old; 65 individuals were Caucasian and 65 were descendants of Amerindians. The ethnic origin was assigned according to a questionnaire specially designed and validated for that purpose. Genotyping was performed using RFLPs: PCR reaction, followed by MspI (-1639G>A) or StyI(1173C>T) digestion. Differences in allele frequencies among racial groups were compared with Chi square test.Results: SNPs frequencies were A) 1639G>A: 20 GG, 27 AG, 18 AA in Caucasians and 16 GG, 36 AG, 13 AA in descendants of Amerindians and B) 1173C>T: 18 CC, 29 CT, 18 TT in Caucasians and 14 CC, 41 CT, 10 TT in descendants of Amerindians. Differences between groups were not significant (Chi square P = 0.281 and P = 0.089 respectively).Conclusion: Although the differences between the ethnic groups analyzed were not significant, higher proportion of heterozygotes were found in descendants of Amerindians for both SNPs. The number of subjects included in this preliminary analysis could be insufficient to show significant differences. Moreover, the method applied to assign the ethnic characteristics would imply some degree of ethnic misclassification.In order to exclude possible differences between these groups we think that the analysis should be done on a higher number of subjects in whom ethnic assignment is performed by short tandem repeat (STR) markers.