RESUMO
<p><b>OBJECTIVE</b>To investigate the single nucleotide polymorphisms (SNPs) at interleukin 6 (IL-6)-174 and TNF-β NcoI in Chinese Han children in Guangzhou, China and to provide basic information for study on the association between IL-6-174 and TNF-β NcoI polymorphisms and systemic inflammatory response syndrome (SIRS).</p><p><b>METHODS</b>Allele-specific polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism were used to determine the SNPs at IL-6-174 and TNF-β NcoI in 481 children selected from the Han population in Guangzhou in 2012. Genotype analysis and comparison with other populations were made with reference to relevant literature.</p><p><b>RESULTS</b>Chinese Han children in Guangzhou had only GG genotype at IL-6-174, and the SNP at this locus was rare or not seen in the Han population in Guangzhou. At TNF-β NcoI, the frequencies of TNF-β 1*1, TNF-β 1*2, and TNF-β 2*2 genotypes were 24.7%, 49.7%, and 25.6%, respectively. The sample distribution was in accordance with Hardy-Weinberg equilibrium. The TNF-β 1 allele frequency was significantly higher in Guangzhou Han population than in European and American white population (P<0.05).</p><p><b>CONCLUSIONS</b>TNF-β NcoI SNP is prevalent in the Han population in Guangzhou, and the distribution of alleles is significantly different from that in the white population. The sample from an Hardy-Weinberg equilibrium population can be further used for study on the association between TNF-β NcoI SNP and SIRS in Chinese Han children in Guangzhou. IL-6-174 SNP is rare or not seen in the Han population in Guangzhou, so SNP at this locus cannot be selected for disease association analysis.</p>