Single Nucleotide Polymorphism in the IFNG rs1861494 Gene among a Subset of Iraqi Pediatric Patients with Gastroenteritis Co-infected with Cryptosporidium and Adenovirus

Abstract

Background: Research identifies enteric adenoviruses as the third most common cause of infantile gastroenteritis, while Cryptosporidium causes parasitic gastroenteritis. Many studies have revealed the role of IFN-γ in inflammation and autoimmune diseases. Objective: To investigate the IFNG rs1861494 gene polymorphism among Iraqi pediatric patients with gastroenteritis co-infected with cryptosporidium and adenovirus. Method: This case-control study enrolled 75 pediatric patients with severe gastroenteritis, whose ages ranged from 3–120 months and had a mean age of 30.64 months. The apparently healthy control (AHC) in this study included 25 pediatric individuals with a mean age of 27.64 months. We extracted DNA from stool specimens to further extract total genomic DNA, extract the human adenovirus (HADV) viral genome via PCR, and detect the IFNG rs1861494 polymorphism using the ARMS PCR technique. Results: The male gender percentage in patients and AHC groups was 54%, while the female counterpart was 46%. The positive PCR result for HADV7 was 28%, whereas the positive result for Cryptosporidium was 6%. In the studied groups, the GG genotype increased at a rate OR=2.67 as compared to the AG and AA genotypes. HADV7 and Cryptosporidium showed a strong correlation with the SNP IFNG rs1861494 results in gastroenteritis (r=0.968, p=0.007 and r=0.984, p=0.008). Conclusions: The identified enteric co-infection of Cryptosporidium and HADV-7, as well as the IFNG rs1861494 polymorphism, may shed light on possible pathogenic roles in gastroenteritis.