Objective: To investigate the possible role of the UGT1A1 G71R or the OATP2 A388G genes mutation with coexisting G-6-PD deficiency in occurrence of neonatal hyperbilirubinemia.
Methods: Totally 109 umbilical cord blood samples were collected for the screening of G-6-PD activity by nitroblue tetrazolium (NBT) test and identification of G71R gene type by polymerase chain reaction combined with allele-specific oligonucleotide assay (ASO-PCR). At the same time, for 101 of the 109 cord blood samples A388G gene types were tested by restriction fragment length polymorphism (RFLP). According to G-6-PD activity and G71R or A388G genotype, the neonates were allocated into different groups. The authors compared the incidence rate of hyperbilirubinemia among different groups. Ten samples were sequenced to validate the results.
Results: Among the 109 umbilical cord blood specimens, the allele frequency of G71R was 22.03% in G-6-PD deficient group, 28.0% in G-6-PD normal group. The incidence rate of neonatal hyperbilirubinemia for those neonates who were G-6-PD deficient with coexisting homozygous or heterozygous variant of the G71R gene was significantly higher than that of neonates who were G-6-PD normal and had wild type G71R gene type, chi(2) = 10.45, P = 0.0012. The odds ratio (OR) of the former was 18.00 (95% CI: 2.12, 152.9). Among the 101 neonates, the allele frequency of A388G was 20.0% in G-6-PD deficient group and 18.5% in G-6-PD normal group. The incidence rate of neonatal hyperbilirubinemia for those neonates who were G-6-PD deficient with coexisting homozygous or heterozygous variant of the A388G gene was significantly higher than that of the neonates who were G-6-PD normal and had wild type A388G gene type, chi(2) = 10.39, P = 0.0013. The OR of the former was 11.8 (95% CI: 2.15, 56.48).
Conclusion: G-6-PD deficiency coexists with G71R or A388G mutation in some individuals in Guangxi region. UGT1A1 G71R gene mutation combined with G-6-PD deficiency or A388G gene mutation combined with G-6-PD deficiency may play a coordinative role in the development of neonatal hyperbilirubinemia.