[DNA polymorphisms and haplotypes in the apoAI-CIII gene region and coronary heart disease]

Abstract

Polymorphisms and haplotypes identified by DNA Restriction Fragment Length Polymorphisms in the apoAI-CIII gene region were investigated both in 33 Chinese patients with coronary heart disease and 50 unrelated healthy subjects, using genomic DNA hybridization analysis with a 1.0 kb fragment of the human apoAI gene cDNA. The frequencies of the S2 and M2 alleles were 0.167 and 0.22 in healthy subjects, 0.11 and 0.24 in patients respectively. There were no differences in the frequencies of the S2 and M2 alleles between patients and healthy subjects. Since none of the subjects had the genotypes, S1S2M1M1, S2S2M1M2 and S2S2M1M1, all of the S2 alleles were considered to be associated with the M2 alleles at least in Chinese population. The alleles identified by the apoCIII Sst-I and apoAI Msp-I polymorphisms are in linkage disequilibrium. The individuals with the haplotype S1-M2 were significantly increased in patients compared with the ones in healthy subjects (26% versus 4.6%; chi 2 = 6.91, d.f = 1, P less than 0.01). The results of the present study suggest that both the apoCIII Sst-I and apoAI Msp-I polymorphisms may be a useful genetic marker for the analysis of apoAI-CIII gene complex and the haplotype S1-M2 may be a useful linkage marker for the putative atherogenic gene in Chinese.