To analyze the association of the polymorphisms of xeroderma pigmentosum complementation group D (XPD) and 8-oxoguanine glycosylase-1 (OGG1) genes with the risk of age-related cataract (ARC) in an Egyptian population.
This case-control study included 150 patients with ARC and 50 controls. Genotyping of XPD Asp312Asn was performed by amplification refractory mutation system PCR assay and genotyping of OGG1 Ser326Cys was carried out by PCR including confronting two-pair primers.
The Asn/Asn genotype of XPD gene was significantly associated with increased risk of ARC (odds ratio [OR] = 2.74, 95% confidence interval [CI] = 1.01–7.43, p = 0.04) and cortical cataract (OR = 5.06, 95% CI = 1.70–15.05, p = 0.002). The Asn312 allele was significantly associated with an increased risk of ARC (OR = 1.75, 95% CI 1.06–2.89, p = 0.03) and cortical cataract (OR = 2.81, 95% CI = 1.56–5.08, p<0.001). The OGG1 Cys/Cys genotype frequency was significantly higher in ARC (OR = 4.13, 95% CI = 0.93–18.21, p = 0.04) and the Cys326 allele (OR = 1.85, 95% CI = 1.07–3.20, p = 0.03). Moreover, the Cys/Cys genotype of the OGG1 gene was significantly higher in cortical cataract (OR = 6.00, 95% CI = 1.24–28.99, p = 0.01) and the Cys326 allele was also significantly associated with cortical cataract (OR = 2.45, 95% CI = 1.30–4.63, p = 0.005).
The results suggest that the Asn/Asn genotype and Asn312 allele of XPD polymorphism, as well as the Cys/Cys genotype and Cys326 allele of the OGG1 polymorphism, may be associated with increased risk of the development of ARC, particularly the cortical type, in the Egyptian population.