Interleukin (IL) 1beta and IL-10 gene polymorphism in chronic hepatitis C patients with normal or elevated alanine aminotransferase levels.

OBJECTIVE: To evaluate the frequency of cytokine gene single nucleotide polymorphisms (SNP) of IL-1beta and IL-10 at promoter sites -115 and -1082 respectively and their association with hepatocellular injury as suggested by alanine aminotransferase (ALT) level. METHODS: Fifty six patients (31 males, 25 females) positive for HCV antibody were studied. Their mean age was 37.5 +/- 12.0 years (range 16-62). Fifty one were HCV RNA positive; 14 had normal and 37 elevated ALT levels. Type 3 was the predominant genotype. For cytokine polymorphism DNA was extracted from the whole blood. After amplification with polymerase chain reaction, biallelic polymorphisms of IL-1beta at -115 and IL-10 at -1082 promotor site were determined using sequence specific oligonucleotide primers. RESULTS: IL-1beta-15 C allele was present in 49 (87.5%) and -115 T in 30 (53.6%) patients. Genotype CC was present in 26 (46%), TC 23 in (42%), and TT in 07 (12%). IL-10 -1082 A allele was seen in 50 (89.3%) and -1082 G in 35 (62.5%). Genotype AG in 29 (52%), AA in 21(37%), and GG in 06 (11%). Though greater number of HCV RNA positive patients with normal ALT had IL-10 -1082 AG genotype (10 out of 14), no statistically significant difference could be found in the genotype profile of the above promoter sites of IL-1beta and IL-10 in patients with normal or elevated ALT. CONCLUSION: IL-1beta-115 C and IL-10 -1082A are the more frequent alleles in our patients. Genotypes L-1beta -115 CC and TC, and IL-10 -1082AG and AA are common while -115 TT and -1082 GG are less common. Any effect of IL-1beta and IL-10 gene polymorphism on the degree of hepatocellular injury may not be apparent by the ALT levels.