# Polymorphisms in oxidative pathway related genes and susceptibility to inflammatory bowel disease

## TL;DR

This study investigates how genetic variations in oxidative pathway genes may affect the risk of inflammatory bowel disease in the Moroccan population.

## Contribution

The study is the first to assess the role of NOS2A, HIF1A, and NFKB1 polymorphisms in IBD susceptibility in a Moroccan population.

## Key findings

- NOS2A_(CCTTT)n polymorphisms showed significant differences in allele frequencies between IBD patients and healthy controls.
- Specific (CCTTT) repeat alleles were associated with increased risk for Crohn's disease and ulcerative colitis.
- HIF1A and NFKB1 polymorphisms did not show significant associations with IBD susceptibility.

## Abstract

To better characterize the genetic factors, implicated in oxidative pathway, determining susceptibility to inflammatory bowel disease (IBD), we assessed for the first time the potential role of NOS2A, HIF1A and NFKB1 polymorphisms on the risk of developing IBD in Moroccan population.

The distribution of (TAAA)n_rs12720460 and (CCTTT)n_rs3833912 NOS2A microsatellite repeats, HIF-1A_rs11549467 and NFKB1–94ins/delATTG_rs28362491 was analyzed in 507 subjects grouped in 199 IBD and 308 healthy controls. Genotyping was performed with polymerase chain reaction-fluorescent method and the TaqMan® allelic discrimination technology.

The allele and genotype frequencies of HIF1A_rs11549467, NFKB1_rs28362491 and NOS2A_(TAAA)n did not differ significantly between patients and controls. Analysis of NOS2A_(CCTTT)n markers evidenced differences between patients and healthy controls. A preferential presence of the (CCTTT)8 (P=0.02; OR=1.71, 95%CI=1.07–2.74), (CCTTT)14 (P=0.02; OR=1.71, 95%CI=1.06–2.76) alleles in IBD, (CCTTT)8 (P=0.008; OR=1.95, 95%CI=1.17–3.23) in CD and (CCTTT)7 (P=0.009; OR = 7.61, 95%CI=1.25-46.08), (CCTTT)11 (P=0.05 ; OR= 0.51, 95%CI=0.25-1.01), (CCTTT)14 (P=0.02 ; OR= 2.05, 95%CI=1.07-3.94), (CCTTT)15 (P=0.01 ; OR= 2.25, 95%CI=1.16-4.35) repeats in UC patients indicated its possible association with higher disease risk which need to be confirmed in a larger sample size.

Our results suggest that the NOS2A_(CCTTT)n gene variations may influence IBD susceptibility in the Moroccan population.