title: Polymorphisms of DNA repair genes OGG1 and XPD and the risk of age-related cataract in Egyptians.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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 Cys(³²⁶ 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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
authors.forename: Amal F
authors.initials: AF
authors.lastname: Gharib
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
authors.forename: Sherif A
authors.initials: SA
authors.lastname: Dabour
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
authors.forename: Rasha L
authors.initials: RL
authors.lastname: Etewa
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
authors.forename: Rania A
authors.initials: RA
authors.lastname: Fouad
mesh_terms: D000368:Aged; D000375:Aging / Q000235:genetics; D000483:Alleles; D016022:Case-Control Studies; D002386:Cataract / Q000201:enzymology* / Q000235:genetics*; D045647:DNA Glycosylases / Q000235:genetics*; D004260:DNA Repair / Q000235:genetics*; D003710:Demography; D004534:Egypt; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D051759:Xeroderma Pigmentosum Group D Protein / Q000235:genetics*
chemical_list: D045647:DNA Glycosylases; C479058:oxoguanine glycosylase 1, human; D051759:Xeroderma Pigmentosum Group D Protein; C497292:ERCC2 protein, human