Investigation of Scavenger Receptor Class B Type I gene variants in patients with coronary heart disease with a history of early myocardial infarction

OBJECTIVE
The scavenger receptor class B type 1 (SR-BI, SCARB1), which is a high-density lipoprotein (HDL) receptor that mediates selective cholesteryl ester uptake, plays an important role in reverse cholesterol transport. This study investigated the distribution of polymorphic variants of the SR-BI gene in patients with coronary heart disease (CHD) with a history of early myocardial infarction (MI) at an early age and their effects on their serum lipid levels.

METHODS
SR-BI rs5888(T>C), rs4238001(C>T), and rs10846744(G>C) were analyzed in 100 male patients with CHD with a history of MI (MI+) who were younger than 50 years and 89 male control subjects without MI history (MI−) using real-time polymerase chain reaction (PCR) and mutant-allele–specific PCR techniques.

RESULTS
SR-BI rs4238001 common-CC genotype was found to be more frequent in patients with MI+ than in control subjects (MI−; odds ratio 4.046, p<0.001). The rs10846744 rare-C allele showed a significant association with increased total cholesterol (p=0.014) and triglyceride (p=0.009) levels in the MI+ CHD group. Logistic regression analysis confirmed that there may be an association between the rs4238001-CC genotype (p=0.002), smoking (p=0.026), and MI+ CHD in the presence of other risk factors associated with CHD, whereas haplotype analysis confirmed that patients with MI+ CHD (rs5888-C, rs10846744-G, and rs4238001-C alleles) and CCC (rs5888-C, rs10846744-C, and rs4238001-C alleles) haplotypes were highly frequent (p<0.01 and p=0.027, respectively).

CONCLUSION
These results indicated that SR-BI gene variants show different distribution in patients with MI+ CHD compared with that in MI– control subjects, and these variants may have effects in favor of dyslipidemia.