Association between MBOAT7 rs641738 polymorphism and non-alcoholic fatty liver in overweight or obese children

The association between non-alcoholic fatty liver (NAFL) and the variant rs641738 within the membrane bound O-acyltransferase domain-containing 7 (MBOAT7) gene is currently uncertain, especially in the paediatric population. We examined whether there is an association between this genetic variant and NAFL in a large multicentre, hospital-based cohort of Italian overweight/obese children.

We studied 1760 overweight or obese children [mean age (SD): 11.1(2.9) years, z-body mass index (zBMI) 3.2(0.9)], who underwent ultrasonography for the diagnosis of NAFL. A subgroup of these children (n = 182) also underwent liver biopsy. Genotyping of the MBOAT7 rs641738 polymorphism was performed by TaqMan-Based RT-PCR system in each subject. Overall, 1131 (64.3%) children had ultrasound-detected NAFL; 528 (30%) had rs641738 CC genotype, 849 (48.2%) had rs641738 CT genotype, and 383 (21.8%) had rs641738 TT genotype, respectively. In the whole cohort, the interaction of MBOAT7 genotypes with zBMI was not associated with NAFL after adjustment for age, sex, serum triglycerides, serum alanine aminotransferase levels and patatin-like phospholipase domain-containing protein-3 (PNPLA3) genotype (adjusted-odds ratio 1.02 [95% CI 0.98-1.06]). Similarly, no association was found between MBOAT7 genotypes and NAFL after stratification by obesity status. MBOAT7 genotypes were not associated with the presence of non-alcoholic steatohepatitis or the stage of liver fibrosis in a subgroup of 182 children with biopsy-proven NAFLD.

The results of this study did not show any significant contribution of MBOAT7 rs641738 polymorphism to the risk of having either NAFL on ultrasonography or NASH on histology in a large hospital-based cohort of Italian overweight/obese children.