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, Interleukin-6 - genetics, Heterozygote, Genetic Predisposition to Disease, Gene Frequency - genetics, Ethnic Groups - genetics, Coronary Disease - genetics, Case-Control Studies, Asian Continental Ancestry Group - genetics, Alleles, Polymorphism, Single Nucleotide - genetics