Studies that used common variants in PNPLA3, TM6SF2 and GCKR as instruments to investigate the relationship between NAFLD and coronary artery disease (CAD) have reported contrasting results.
There was a significant difference in the distribution of genotype and allele of TM6SF2rs58542926 in NAFLD and NAFLD&CRA patients compared to controls.
Here, we accessed the seven polymorphisms of rs1260326, rs780094 in GCKR, rs2954021 near TRIB1, rs2228603 in NCAN, rs58542926 in TM6SF2, rs12137855 near LYPLAL1, and rs10883437 near CPN1 on NAFLD susceptibility in the Uygur population.
Nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) share risk factors, and recent meta-analysis confirmed that NAFLD is an independent risk factor for incident CKD.<sup>1</sup> Genetic variants associated with NAFLD, such as patatin-like phospholipase domain-containing-3 (PNPLA3) rs738409<sup>2</sup> and transmembrane 6 superfamily member 2 (TM6SF2) rs5854292,<sup>2</sup> have been reported to be associated with renal function in NAFLD subjects.
Among the 9342 participants with available genetic and aminotransferase data, the PNPLA3 G allele (odds ratio [OR], 1.53; 95% CI, 1.41-1.66), TM6SF2 T allele (OR, 1.41; 95% CI, 1.20-1.67), and PPP1R3B G allele (OR, 1.16; 95% CI, 1.06-1.28) were associated with suspected NAFLD.
Second, although the strongest genetic risk alleles for NAFLD (ie, the 148Met allele in PNPLA3 and the 167Lys allele in TM6SF2) are associated with increased liver fat content and progression to NASH and cirrhosis, these alleles are also unexpectedly associated with an apparent protection from cardiovascular disease.
BA and fibroblast growth factor 19 (FGF19) levels (a surrogate for intestinal farnesoid X receptor [FXR] activity), patatin-like phospholipase domain-containing 3 (PNPLA3) and transmembrane 6 superfamily member 2 (TM6SF2) variants, and gut microbiota profiles in lean and non-lean NAFLD were investigated in a cohort of Caucasian patients with biopsy-proven NAFLD (n = 538), lean healthy controls (n = 30), and experimental murine models.
New polymorphisms, such as those in PNPLA3, TM6SF2, MBOAT7 and GCKR, have been identified and used to predict the development and severity of NAFLD in both adults and children, and their interaction with environmental factors has been elucidated.
Importantly, our data indicates that the genetic variant TM6SF2E167K, previously associated with increased risk for NAFLD, induces increased hepatocyte fat content by reducing APOB particle secretion.
<i>TM6SF2, GCKR</i><i>,</i> and <i>MBOAT7</i> risk alleles did not show any impact on kidney function, while the <i>PNPLA3</i> G allele was associated with lower eGFR, but only in children with NAFLD (<i>p</i> = 0.003).
An I148 M variant in patatin-like phospholipase domain-containing protein 3 (PNPLA3) and an E167K variant in transmembrane 6 superfamily 2 (TM6SF2) are major genetic risk factors for the development and progression of NAFLD.
Recent genome-wide association studies have identified 2 genetic polymorphisms in association with nonalcoholic fatty liver disease (NAFLD): patatin-like phospholipase domain containing 3 (PNPLA3) and transmembrane 6 superfamily member 2 (TM6SF2), both of which appear to influence the production of very low density lipoprotein (VLDL).
And, our data suggested a strong link between the TM6SF2E167K variant and the risk of NAFLD in a dominant model (CT + TT, OR = 2.327, 95% CI: 1.542-3.513, P = 0.000).
However, recent progress on the genotype/phenotype relationships in NAFLD patients indicates the development of NAFLD with a relative conservation of glucose metabolism in individuals with specific gene variants, such as the patatin-like phospholipase domain-containing 3 (PNPLA3) and transmembrane 6 superfamily member 2 protein (TM6SF2) variants.
Therefore, we investigated the impact of MetS, PNPLA3 rs738409, TM6SF2rs58542926 and MBOAT7 rs641738 on overall and cardiovascular disease (CVD) specific mortality among subjects with or without NAFLD.
These results suggested that TM6SF2rs58542926 could be used to identify individuals at higher susceptibility to chronic liver disease, especially for HCC, cirrhosis, ALD, and NAFLD.
Among the eleven genotyped SNPs, the genetic variants in TM6SF2rs58542926 (OR = 4.13, p = 0.002), GCKR rs1260326 (OR = 1.53, p = 0.003), PNPLA3 rs738409 (OR = 1.58, p = 0.004) and ELOVL2 rs2236212 (OR = 1.34, p = 0.047) were significantly associated with a higher risk of NAFLD.
In non-obese NAFLD patients, the frequency of the PNPLA3 p.I148M allele (74.6%), but not of the TM6SF2 or MBOAT7 polymorphisms, was significantly (P < 0.05) higher as compared to the other patients in the NAFLD CSG cohort (54.9%) or controls (40.2%).
As variants in PNPLA3 (I148M) and TM6SF2 (E167K) are associated with nonalcoholic fatty liver disease, we assessed these variants in type 2 diabetes (T2D) patients randomized to receive BIL (n=1822) or GL (n=1270) in three phase 3 trials.