Superoxide Dismutase (SOD1) Gene Polymorphism in Cataract Patients of Karachi, Pakistan

Abstract

Objective: To investigate the polymorphism superoxide dismutase (SOD1) gene and its relationship with the development of cataracts in patients of Karachi. Methods: This was a case-control study carried out at different centers in Karachi, Pakistan between September 2019 and 2020. A single nucleotide polymorphism (SNP) at rs2070424(SOD1) locus was examined with polymerase chain reaction (PCR) using high resolution melting curve (HRM) technique in 250 cataract patients and 250 healthy control groups of similar age and gender. Results: Of 500 subjects, there were 250 cases and 250 controls. The mean age of the cataract patients (cases) was 43.97± 13.36 years. Among cases, 150 (60.0%) were males and 100 (40.0%) were females whereas in controls, 127 were males (50.8%) and 123 (49.2%) were females. A significant association of cataract was found with age (p value = 0.005), and smoking (p-value = 0.001). AG genotype has a smaller risk (OR=1.77, 95% CI 1.11 – 2.66, p-value= 0.006) associated with cataract while GG has a higher risk (OR = 2.83, 95% CI 1.71 – 4.68, p-value < 0.001). Further, calculation of allelic distribution revealed that the G allele was more prevalent in the cataract group 200 (61.7%) as compared to controls 124 (38.3%) (p-value=0.001). Conclusion: The significantly higher G allele frequency in the SOD1 gene at the rs2070424(SOD1) locus in the cataract group indicates that potential risk factors contribute to cataracts' development. This study contributes to the genetic profiling of cataract patients in the Pakistani population.

Keywords

• Cataract, Polymerase Chain Reaction, Polymorphism, Reactive Oxygen Species, Superoxide Dismutase, Single Nucleotide.