Background: Recent studies have shown that elevated plasma interleukin-6 (IL-6) levels in coronary heart disease (CHD) patients are associated with polymorphisms in the promoter region of the IL-6 gene. However, related studies of these phenomenon are rare in the Han population of China. The aim was to develop a rapid IL-6 gene genotyping assay by fluorescent resonance energy transfer (FRET) and melting curves on a LightCycler system and then study the association between IL-6 gene polymorphisms and CHD.
Material and Method: Two hundred thirty-one CHD patients and 210 controls, all of Han ethnicity from northern China, were analyzed by the established method. DNA sequencing analysis confirmed the results.
Results: Three genotypes were found for the -572G/C polymorphism in the Han Chinese. Statistical analysis for the this polymorphism revealed a significant difference between G allele carriers (GG+GC) and non-G allele carriers (CC) in both the CHD and the control group. Ten cases were identified to be of GA genotype for the -597G/A polymorphism in the Han Chinese. PCR product sequencing confirmed all the results.
Conclusions: A rapid IL-6 gene genotyping assay was developed. The clinical data revealed that the -572G/C polymorphism in the IL-6 gene promoter region is involved in the pathogenesis and progression of CHD in the Han Chinese.

Keywords: Nucleic Acid Denaturation - genetics, Middle Aged, Interleukin-6 - genetics, Male, Humans, Heterozygote, Genetic Predisposition to Disease, Gene Frequency - genetics, Female, Ethnic Groups - genetics, Coronary Disease - genetics, Case-Control Studies, Asian Continental Ancestry Group - genetics, Alleles, Aged, Adult, Polymorphism, Single Nucleotide - genetics