Comparison of molecular mutations of G6PD deficiency gene between icteric and nonicteric neonates

Background and Aim: Jaundice is a common disorder in neonates and one of the provable causes of glucose-6-phosphate dehydrogenase (G6PD) deficiency, some mutation types of which may be associated with severe neonatal icter. In this line, the present study has been conducted to compare G6PD mutations in incteric and non icteric neonates. Materials and Methods: This case-control study was implemented in the NICU and Newborn Ward of Amirkola Children Hospital in 2007-2008. Available sampling approach was used and 50 icteric as well as 50 non-icteric newborns, both with G6PD deficiency, were selected as the case and the control group respectively. Two milliliters of peripheral blood were collected in EDTA-containing tubes after parental consent and G6PD deficiency was diagnosed using FST (Fluorescent Spot Test) method. All samples were first evaluated in terms of Mediterranean mutation and the negative cases of this mutation were then examined for Chatham mutation all remaining samples were finally tested for Cosenza mutation. After the completion of the above steps, G6PD mutations were compared in the two groups and P-value less than 0.05 was considered significant. Results: In icteric group, 76% were male and 24% were female and in non-icteric group, 70% were male and 30% were female. The mean weight of neonates was 3.2 ± 0.4 kg and 2.8 ± 0.8 kg in icteric and non-icteric groups respectively (p0.05), however, the distribution of rare mutations (Cosenza negative) was significantly different between icteric and non-icteric groups with enzyme deficiency (p 0.05). Newborns with Chatham mutation have been less in need of exchange transfusions (p <0.05). Conclusions: Findings of the present study showed that there was no significant relationship between prevalent mutations of G6PD gene and the incidence of icter in Mediterranean and Chatham mutations Mediterranean mutation was the most common mutation in the mentioned gene in icteric and non-icteric neonates in our region, while Cosenza mutation was more frequent in non-icteric group, indicating that rare mutations of G6PD gene may less likely lead to neonatal icter. Furthermore, the need for exchange transfusion is less in icteric neonates with Chatham mutation which is indicative of milder clinical phenotype in this type of mutation.