[ACE gene polymorphisms associated with serum ACE activity in the Henan Hans of China]

In order to investigate the relationship between gene polymorphisms and serum activity of the angiotensin-1 converting enzyme(ACE) in Chinese population, eight loci in ACE gene were detected by polymerase chain reaction combined with restriction fragment length polymorphism or electrophoresis directly, and serum ACE activity was measured by spectrophometry. Using maximum likelihood estimation(MLE), the pattern of intragenic linkage disequilibrium and the haplotype structure were estimated. All the eight polymorphisms formed nine haplotypes,in which the two most frequent haplotypes were A (A-T-A-T-G-I-A-3) and B(C-C-T-C-A-D-G-2). Also haplotype A and haplotype B were completely different at all eight sites. Deduced from the maximum-parsimony tree,the haplotypes in Chinese population could be grouped into three clades. Clade III seemed to be generated by an ancestral recombination event between clade I and clade II. Every locus formed, the haplotype B was associated with high ACE activity. This findings suggested that serum ACE levels were partially determined by genetic predisposition (the polymorphism of ACE gene). Haplotype B may be related to the quantitative trait loci of high-level activity,whereas high-resolution genetic mapping linked with ACE was still necessary to characterize definitely the functional variants.