Objective: To identify single nucleotide polymorphisms (SNP) in the regulatory and coding regions of human kynureninase (KYNU) gene in a hypertensive candidate chromosomal region 2q14-q23 of Han Chinese, and to investigate the relationship between polymorphisms in KYNU and essential hypertension.
Methods: The SNPs in the promoter region and exons of the KYNU gene were detected by direct DNA sequencing. Genotyping of the nonsynonymous Lys412Glu (A/G) polymorphism was performed by DHPLC technology in 456 hypertensive patients and 430 normal controls.
Results: Sixteen SNP were identified in the KYNU gene, including 6 in the regulatory region and 2 in the coding region (both of them lead to substitution of amino acid). Significant differences between hypertensive patients and normal controls were observed for the distribution of alleles (chi(2) = 6.693, P = 0.035) and genotypes (chi(2) = 4.188, P = 0.041) of the Lys412Glu polymorphism in all subjects, and for the distribution of alleles in the subgroup of men (chi(2) = 4.424, P = 0.035).
Conclusion: The Lys412Glu polymorphism of the KYNU gene in a hypertensive candidate chromosomal region is associated with essential hypertension in Han Chinese.