Abstract: Abstract： Objective To investigate the association between plasma homocysteine (Hcy) levels and cystathionine β synthase (CBS) T833C gene polymorphism with essential hypertension in Xinjiang Kazakh and Han populations. Methods A total of 239 Kazak patients with hypertension (Kazak EH group), 206 Kazak people with normal blood pressure (Kazak con⁃ trol group), 256 Han patients with hypertension (Han EH group) and 206 Han people with normal blood pressure (Han con⁃ trol group) were selected for the study. Amplification refractory mutation system(ARMS) was used to analyze the polymor⁃ phism of CBS gene T833C， TT， TC and CC genotypes and the various sites of T， C allele frequencies in four groups. In the meantime, the Hcy level and related biochemical indices were detected using automatic biochemical analyzer. Results The plasma Hcy levels were significantly higher in Kazak EH group and Han EH group than those of Kazak control group and Han control group (P < 0.05). The C allele frequencies were significantly higher in Kazak EH group than that of Kazak control group (P < 0.05). The plasma level of Hcy was significantly lower in Kazakh and Han people with TT genotypes than that of TC genotypes (P < 0.05). There were no significant differences in the frequency of genotypes and alleles between Han EH group and Han control group (P > 0.05).Conclusion The Cystathionine β synthase gene of T833C polymorphism may be associated with essential hypertension in Kazak people in Xinjiang, but no such association in Han population in Xinji⁃ ang. The mechanism may be related to the altered metabolism of Hcy induced by CBS mutation.

Key words: hyperhomocysteinemia, cystathionine beta- synthase, polymorphism, genetic, hypertension, Han
nationality, Kazakh nationality