PHYSIOLOGICAL RESEARCH ISSN 0862-8408 © 2004 Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic Fax +420 241 062 164 E-mail: physres@biomed.cas.cz http://www.biomed.cas.cz/physiolres Physiol. Res. 53: 215-218, 2004 SHORT COMMUNICATION Effect of C677T Methylenetetrahydrofolate Reductase Gene Polymorphism on Plasma Homocysteine Levels in Ethnic Groups J. GAŠPAROVIČ, K. RAŠLOVÁ, Z. BAŠISTOVÁ 1 , M. ZACHAROVÁ 1 , L. WSÓLOVÁ, M. AVDIČOVÁ 2 , P. BLAŽÍČEK 3 , J. LIETAVA 4 , D. SIVÁKOVÁ 1 Institute of Preventive and Clinical Medicine, 1 Department of Anthropology, Faculty of Natural Sciences, Comenius University, 2 State Institute of Health, Banská Bystrica, 3 Military Hospital, 4 Department of Medicine Teaching Hospital, Bratislava, Slovak Republic Received August 22, 2002 Accepted May 12, 2003 Summary The objective of this study was to examine plasma homocysteine levels and C677T methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in two ethnic groups from Slovakia. The samples consisted of general Slovak-Romany population (68 men and 81 women) from Southwestern Slovakia and the Slovak-Caucasians (174 men and 177 women) who participated in the CINDI project. The homocysteine levels were examined by HPLC, the analysis of MTHFR genotypes was done by PCR. The Slovak-Romany men (12.0±5.6 (S.D.) µmol/l) and women (9.2±2.6 µmol/l) have significantly lower plasma homocysteine levels (p<0.024 and p<0.00001) when compared to Caucasians (13.3±5.1 µmol/l in men and 11.3±4.3 µmol/l in women). The genetic equilibrium is assumed for the gene frequencies of the MTHFR polymorphism in both samples. The distribution of MTHFR genotypes did not differ between the two populations (TT 13 vs. 10.6 %; CT 46.6 vs. 41.7 %; CC 40.4 vs. 47.7%, χ 2 = 2.315, df=2, ns). The effect of MTHFR genotypes on homocysteine levels was not confirmed in the Slovak-Romanies and TT homozygosity significantly increased plasma homocysteine levels only in Slovak-Caucasians (11.5±4.4 μmol/l, ns; vs. 14.8±4.8 μmol/l, p<0.002, respectively). To our knowledge, this is the first epidemiological study in the Romany population examining distribution of the MTHFR genotypes and their effect on homocysteine levels. Further studies are needed to establish the variety of cardiovascular risk factors among Romanies in order to evaluate the significance of particular factors. Key words C677T methylenetetrahydrofolate reductase polymorphism • Homocysteine • Slovak-Romanies • Slovak-Caucasians • Ethnic groups Plasma homocysteine levels are influenced by many dietary and environmental factors as well as genetically based alterations of homocysteine transsulphurylation or remethylation (Lynch et al. 1995, Toborek and Henneig 1996). The decreased activity of the enzyme 5,10-methylenetetrahydrofolate reductase