Exploring Genetic Variability in VDR FokI and BsmI Polymorphisms and Their Association with Rheumatoid Arthritis.

Background: Rheumatoid Arthritis (RA) is a chronic, inflammatory autoimmune disease that mainly affects small joints and progresses to larger joints. It impacts approximately 1% of the global population, with women being three times more likely to develop it than men, typically between ages 40 and 50. Genetic and environmental factors, including vitamin D deficiency, contribute to RA development. The vitamin D receptor (VDR) gene plays a crucial role in regulating metabolism and inflammation, making it a key candidate in RA. Aims: This study determines the relationship between VDR FokI (rs10735810) and VDR BsmI (rs1544410) gene polymorphisms in RA patients and healthy controls. Methods: A total of 400 participants were included in the study, consisting of 200 RA patients and 200 healthy controls. Genetic varations of VDR genes was performed using the PCR-RFLP technique. Result: Among 200 RA patients, 42 (21%) were male and 158 (79%) were female, while in the control group, 40 (20%) were male and 160 (80%) were female. The average age of RA patients was 43±17 years and a mean disease onset at age 30.3±19.3 years. The Ff and ff genotypes of the FokI polymorphism were significantly more frequent in RA patients (OR=1.8, p=0.011 and OR=2.8, p=0.004, respectively). For the BsmI polymorphism, the Bb genotype showed a significant association with RA (OR=1.5, p=0.049), while the bb genotype did not (OR=1.4, p=0.241). Gender-based analysis revealed higher frequencies of the Ff, ff, and bb genotypes in females, with significant associations for Ff (OR=3.0, p=0.009), ff (OR=4.5, p=0.002) for Bsml genotype only bb (OR=3.9, p=0.006) was significantly increase the risk of RA. Conclusions: This study concluded that the VDR FokI (rs10735810) gene polymorphism was associated with RA, while the VDR BsmI (rs1544410) polymorphism did not appear to have a significant association with the disease.