Genetic factors play an important role in individual susceptibility to hepatitis C. The alpha-1 antitrypsin (A1AT) gene, encoded by the SERPINA1 gene, protects liver tissue, but its variants, PiS and PiZ, negatively affect liver function.

Participants were divided into two groups of hepatitis C patients and controls. Each group consisted of 68 cases. In the study group, there were 8 females and 60 males, and in the control group, there were 39 females and 29 males. DNA was extracted from peripheral blood samples, and routine laboratory tests, including alanine aminotransferase (ALT) enzyme, were conducted. The RFLP-PCR technique was used to analyze the two common polymorphisms of this gene, Glu264Val and Glu342Lys (S and Z variants).

The average age of patients and the control group was 41.76 ± 10.61 and 37.39 ± 12.77, respectively. Among patients, 48 had normal ALT levels compared to 57 individuals with normal ALT in the control group. Moreover, the genetic analysis indicated that the frequencies of S and Z variants of A1AT in patients with HCV are higher than in the control group (P < 0.05). In the control group, the frequency of the S variant was 5.77%. In the hepatitis C group, the frequency of the S variant was 23.44%, and this difference is significant after adjustment for confounders. The results of risk factor analysis also illustrated that the frequency of alcohol consumption (41.17%), addiction (47.05%), transfusion (45.58%), and tattooing (35.29%) was significantly higher in patients.

SS and ZZ variants in the group of patients with hepatitis C are significantly more prevalent than in the control group. This higher frequency would presumably be a reason for the increased susceptibility to this type of viral hepatitis.