Background: We studied for the first time among children differences in plasma alanine aminotransferase (ALT) among genotypes of the rs641738 polymorphism in the MBOAT7 gene that has been associated with increased risk of nonalcoholic fatty liver disease among adults. We also investigated the associations of a genetic risk score combining information from the MBOAT7, PNPLA3, and TM6SF2 polymorphisms with plasma ALT.
Methods: We performed a 2-y follow-up study in 467 Caucasian children aged 6-9 y, genotyped the MBOAT7, PNPLA3, and TM6SF2 polymorphisms, calculated a genetic risk score from these polymorphisms (scored 0-3) and assessed plasma ALT.
Results: Children carrying the T allele of the MBOAT7 polymorphism had 7% higher plasma ALT at baseline (17.8 vs. 19.1 U/l, P = 0.022) and 10% higher plasma ALT at 2-y follow-up (18.0 vs. 19.7 U/l, P = 0.022) than the noncarriers. A higher genetic risk score was associated with higher plasma ALT at baseline (17.5, 18.5, 19.2, and 22.8 U/l, P = 0.008 for linear trend) and 2-y follow-up (18.2, 18.9, 18.9, and 32.8 U/l, P = 0.017 for linear trend).
Conclusion: Children carrying the T allele of the MBOAT7 polymorphism had higher plasma ALT than the noncarriers. Children with the MBOAT7, PNPLA3, and TM6SF2 variants had the highest plasma ALT.