Effects of Gene Variants Controlling Vitamin D Metabolism and Serum Levels on Hepatic Steatosis

Background/Aims: Common genetic variations in vitamin
D metabolism are associated with liver stiffness. Whether
these genes are implicated in hepatic steatosis remains unclear.
Here we aimed to analyse the association of common
vitamin D pathway gene variants with liver steatosis. Methods:
Liver steatosis was assessed non-invasively in 241 patients
with chronic liver conditions by controlled attenuation
parameter (CAP). The following polymorphisms were
genotyped using TaqMan assays: group-specific component
( GC ) rs7041, 7-dehydrocholesterol reductase ( DHCR7 )
rs12785878, cytochrome P450 2R1 ( CYP2R1 ) rs10741657,
vitamin D receptor ( VDR ) rs7974353. Chemiluminescence
immunoassay determined serum 25-hydroxyvitamin D
(25(OH) D) concentrations. Results: Vitamin D deficiency
(defined by 25(OH)D concentrations <20 ng/mL) occurred
in 66% of patients. Median CAP was 296 (100–400) dB/m.
Patients with advanced steatosis (CAP ≥ 280 dB/m) had significantly
( p = 0.033) lower 25(OH)D levels as compared to
patients with CAP <280 dB/m. Moreover, the rare allele [T]
in GC rs7041 was significantly ( p = 0.018) associated with
higher 25(OH)D levels in patients with CAP <280 dB/m.
However, GC , DHCR7, CYP2R1 , and VDR polymorphisms
were not related to liver steatosis and obesity traits. Conclusions:
Higher CAP values are associated with low serum
25(OH)D concentrations but not with common vitamin D
pathway gene variants.

Authors:
Malgorzata Jamka, Anita Arslanow, Annika Bohner, Marcin Krawczyk, Susanne Weber, Frank Grünhage, Frank Lammert, Caroline S Stokes
Date Published:
2018-02-07
Journal:
Digestion