Prevalence of Three Common Glucose-6-Phosphate Dehydrogenase Gene Mutations in Neonates in Province of Mazandaran, North of Iran, 2012

In northern provinces of Iran high rates of incidence of glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency have been reported and most of these patients carry one of the three common G6PD gene mutations: Mediterranean, Chatham or Cosenza. The aim of this study was to investigate prevalence of each of these mutations among neonates in Mazandaran, a northern province of Iran. Four hundred and twelve blood samples were collected and using standard protocols DNA was extracted. In order to detect the above mutations PCR-RFLP method was applied. Fiftythree of neonates had G6PD gene mutation (12.9%, CI 95%: 9.66-16.14). About 17% of female and 9% of male newborns were carriers for one of the three common G6PD gene mutations. The Mediterranean type had the highest gene frequency (0.0607) among the three examined mutations. The present study shows around 17% (CI 95%: 11.97-22.03) of Mazandarani female population is carrier for one of the three mutations and since the likelihood of having an affected child in a carrier woman is 1 in every 4 child births, the researchers recommended all women to be screened for the presence of three common G6PD gene mutations prior to pregnancy. Address for correspondence: Hossein Jalali Postal address: Fajr, Keshavarz Blvd, Sari, Iran Telephone: +98 151 341 1103 Fax: +98 151 329 2929 Email: [email protected] INTRODUCTION Glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency is the most common enzymopathy in the world and affects more than 400 million people worldwide. It is a sex linked, recessively inherited disorder (Cappellini and Fiorelli 2008; Mehta et al. 2000). Affected individuals are usually asymptomatic but in some cases, oxidative stress may lead to acute hemolysis. The hemolytic event is usually triggered by ingestion of fava bean. Other presentation of the disorder would be neonatal jaundice which is not hemolytic in nature (Beutler and Vulliamy 2002;Youngster et al. 2010; Lai et al. 2013; Taki et al. 2001). The gene involved in the disease is located on Xq28, containing 13 exons that encode a protein with 515 amino acids (Beutler 1994). It is estimated that 7.5% of the world population carry one or two mutated G6PD gene, with a prevalence spectrum ranging from 0.1% in Japan and some European countries to 35% in African continent (Beutler 1994; Noori-Daloii et al. 2007). G6PD gene is a highly polymorphic one, and till now about 140 different mutations of the gene have been reported (Cappellini and Fiorelli 2008). G6PD gene mutation distribution rates differ from one geographical area to another. G6PD Avariant, a certain G6PD enzyme deficiency responsible for 90% of the world affected cases is quite common in Italy, the Canary Islands, Spain, Portugal, and in some parts of the Middle East. G6PD A202 (G→A) / 376 (A→G) is the most prevalent mutation in African continent (Cappellini and Fiorelli 2008; Oppenheim et al. 1995; Dallol et al. 2012; Laouini et al. 2013). High incidences of G6PD enzyme deficiency have been reported in some parts of Iran,and the prevalence of the disease varies markedly among different provinces. In northern provinces of Iran, fava bean is a common ingredient of various dishes, and therefore it is not unexpected to have high incidence rate of the disease (8.7%–16.4%) in that region (Mazandaran and Gilan provinces) (Noori-Daloii et al. 2007). A G6PD gene mutation called “Mediterranean” has a wide distribution range, from Mediterranean and Middle Eastern countries to Indian subcontinent. It is the most common mutation among patients from Northern provinces of Iran. Following this mutation, Chatham and © Kamla-Raj 2013 Int J Hum Genet, 13(3): 139-143 (2013)