Frequency of Human Paraoxonase-۱ Q۱۹۲R Polymorphism and Measurement of Oxidative Stress Parameters in Infants with G۶PD Deficiency

Background and Aims: This study aimed to investigate the frequency of Q۱۹۲R polymorphism and oxidative stress markers in infants with glucose-۶-phosphate dehydrogenase (G۶PD) deficiency. Materials and Methods: This is a case-control study in which ۶۰ male infants (۲-۴ months old) with G۶PD deficiency along with ۶۰ age- and sex-matched healthy neonates were included. The diagnosis of G۶PD deficiency was made by Beutler test by which the G۶PD enzyme activity is measured by the fluorescent spot test. The blood samples were taken from all infants, and the sera were isolated for the evaluation of Paraoxonase-۱ (PON۱) and malondialdehyde (MDA) using the spectrophotometric method. Restriction fragment length polymorphism was applied for determination of Q۱۹۲R polymorphism (rs ۶۶۲). Results: The frequencies of QQ, QR, and RR genotypes were ۵۵%, ۳۹%, and ۶%, respectively in infants with G۶PD deficiency while the above genotype frequencies were ۴۵%, ۴۹%, and ۶%, respectively in healthy neonates. The frequency of R and T alleles failed to show any significant difference when G۶PD deficient infants and healthy neonates were compared. The results indicated PON۱ activity and MDA levels being significantly (p<۰.۰۵) higher in neonates with G۶PD deficiency compared with their healthy counterparts. Conclusion: Contrary to previous studies, it was indicated that the presence of RQ and RR genotypes at Q۱۹۲R position is associated with decreased activity of PON۱ and increased oxidative stress. In this study, no significant differences were found in the genotype and allele frequency of PON۱ Q۱۹۲R polymorphism between the case and control groups. Also, this frequency was not consistent with the results obtained from oxidative stress conditions.

Keywords:

G۶PD , Oxidative stress , Polymorphism , پاراکسوناز , مالون دی آلدهید , G۶PD , پلی مورفیسم Q۱۹۲R , استرس اکسیداتیو