Patatin-like Phospholipase Domain-containing 3 Rs738409 Research Articles

Issue highlights

Issue highlights

PNPLA3 rs738409 is not associated with the risk of hepatocellular carcinoma and persistent infection of hepatitis B virus (HBV) in HBV-related subjects: A case-control study and meta-analysis on Asians.

The association between rs738409 (C>G, I148M) with patatin-like phospholipase domain-containing 3 (PNPLA3) gene and the risk of hepatocellular carcinoma (HCC) was controversial in different ethnic populations. Our study aimed to explore the effect of PNPLA3 rs738409 on the risk of HCC and persistent infection of Hepatitis B virus (HBV) in a Chinese HBV-related population, and further evaluate its role in HCC risk among Asians. First, we performed a case-control study by recruiting 786 HBV-related HCC cases, 695 HBV persistent carriers and 719 HBV natural clearance subjects. PNPLA3 rs738409 was genotyped by MassARRAY platform. Second, we conducted a systematic review and meta-analysis on Asians to further validate our results. Our case-control study demonstrated that PNPLA3 rs738409 was not associated with HCC risk or persistent HBV infection (All P>0.05). The subsequent meta-analysis included 13 Asian studies with 9,802 subjects. Results showed that PNPLA3 rs738409 might increase HCC risk among healthy subjects (pooled odds ratio [OR]=1.47, 95% confidence interval [CI]=1.11-1.95), but it had no influence on the development of HCC among HBV-related subjects (pooled OR=1.07, 95%CI=0.89-1.30). Our case-control study highlights that PNPLA3 rs738409 is probably not associated with the risk of HCC or persistent HBV infection in a Chinese HBV-related population. Besides, our systematic review and meta-analysis on Asians further suggest that PNPLA3 rs738409 may confer an increased risk of HCC among healthy people, but contribute little to the development of HCC among HBV-related subjects. Future studies are required to confirm these results.

PNPLA3 gene and kidney disease

Chronic kidney disease (CKD) is a disease regularly seen in clinical practice. At present, CKD is described as a change of kidney structure and/or function and it is classified in relation to cause, values of glomerular filtration rate and albuminuria category. Seeing that CKD is closely linked to the development of end-stage renal disease and other comorbidities, the determination of additional independent predictors for CKD is clinically necessary. At present, there is evidence associating non-alcoholic fatty liver disease (NAFLD) with CKD, thereby suggesting that NAFLD patients may require intensive surveillance to reduce their risk of CKD. In 2008, genome-wide association studies documented an association between the variant rs738409 (C > G p.I148M) in the patatin-like phospholipase domain containing 3 (PNPLA3) gene (mainly implicated in the lipid regulation) and the entire spectrum of NAFLD (i.e., liver steatosis, non-alcoholic steatohepatitis, fibrosis, and hepatocellular carcinoma). In the last years, accumulating epidemiological evidence suggests the existence of a relationship between PNPLA3 rs738409 and risk of CKD, indicating that rs738409 may also contribute to the kidney injury. This is of particular scientific interest, as such association may explain, at least in part, the epidemiological association between liver and kidney disease. In this narrative review, we will discuss the accumulating evidence regarding the association between PNPLA3 rs738409 and risk of CKD, the putative biological mechanisms underpinning such relationship, and the possible future perspective.

PNPLA3 polymorphism influences the association between high-normal TSH level and NASH in euthyroid adults with biopsy-proven NAFLD

AimWe aimed to evaluate the association between serum thyroid stimulating hormone (TSH) levels, within the reference range, and the histological severity of nonalcoholic fatty liver disease (NAFLD), and whether this association was modulated by the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 polymorphism. Materials and methodsWe enrolled 327 euthyroid individuals with biopsy-proven NAFLD, who were subdivided into two groups, i.e., a ‘strict-normal’ TSH group (TSH level 0.4 to 2.5mIU/L; n=283) and a ‘high-normal’ TSH group (TSH level 2.5 to 5.3mIU/L with normal thyroid hormones; n=44). Logistic regression analyses were performed to assess the association between TSH status and presence of nonalcoholic steatohepatitis (NASH) after stratifying subjects by PNPLA3 genotypes. ResultsCompared to strict-normal TSH group, patients with high-normal TSH levels were younger and had a greater prevalence of NASH and higher histologic NAFLD activity score. After stratifying by PNPLA3 genotypes, the significant association between high-normal TSH levels and presence of NASH was restricted only to carriers of the PNPLA3 G risk allele and remained significant even after adjustment for potential confounding factors (adjusted-odds ratio: 3.279; 95% CI: 1.298–8.284; P=0.012). ConclusionIn euthyroid individuals with biopsy-proven NAFLD, we found a significant association between high-normal TSH levels and NASH. After stratifying by PNPLA3 rs738409 genotypes, this association was observed only among carriers of the PNPLA3 G risk allele.

Association of metabolic syndrome and patatin-like phospholipase 3 - rs738409 gene variant in non-alcoholic fatty liver disease among a Chennai-based south Indian population.

Non-alcoholic fatty liver disease (NAFLD) is commonly diagnosed in patients presenting with metabolic syndrome (MetS) and has been associated with single nucleotide polymorphisms of rs738409 in the patatin-like phospholipase domain containing 3 (PNPLA3) gene. This association remains to be investigated in the South Indian population. We aimed to determine the association of the PNPLA3 rs738409 gene polymorphism with MetS and NAFLD among a Chennai-based population. The study comprised 105 NAFLD cases and 102 controls. All subjects were genotyped for the PNPLA3 rs738409 variant and MetS was defined according to the National Cholesterol Education Program - Adult Treatment Panel III criteria. Our case-control study showed the association of the variant with NAFLD and MetS. The PNPLA3 rs738409 variant was associated with NAFLD and the genotype frequencies (CC/CG/GG) were 19 (18.1%), 50 (47.6%) and 36 (34.3%) in the NAFLD group and 59 (57.8%), 29 (28.4%) and 14 (13.7%) in the control group respectively. We also confirmed the interaction between the PNPLA3 rs738409 polymorphism and MetS with respect tto elevated triglyceride levels. However, an association with elevated waist circumference, fasting glucose, blood pressure and decreased high-density lipoprotein cholesterol was not observed in the present study. The PNPLA3 rs738409 gene polymorphism increases the risk of NAFLD by up to four-fold in subjects with an elevated level of triglyceride independent of other features of MetS.

PNPLA3 rs738409 C >G variant is associated with a higher risk of liver fibrosis progression assessed by FIB-4 and stiffness by fibroscan in patients with non-alcoholic fatty liver disease

Background&Aims: A single nucleotide polymorphism in patatin-like phospholipase domain-containing-3(PNPLA3) gene has been associated with a higher prevalence of NASH and severity of fibrosis, hepatocellular carcinoma and liver decompensation, but there are no data from prospective studies about fibrosis progression with this polymorphism.We investigated whether in NAFLD,PNPLA3rs738409 variant associates with fibrosis progession evaluated by noninvasive tools like FIB-4 and liver stiffness measurement(LSM) by FibroScan.

PNPLA3 L148M (rs738409) polymorphism as a risk for new onset diabetes mellitus and obesity in non-NASH/cryptogenic living related donor liver transplant recipients

BackgroundLiver transplantation is considered the main treatment for end stage liver disease and the early stages of hepatocellular carcinoma. Long-term metabolic outcomes after liver transplantation affect morbidity and mortality, and the genetic rule has not been well studied for such complications. The patatin-like phospholipase domain-containing 3 (PNPLA3) gene L148M (rs738409) polymorphism has been associated with a wide spectrum of metabolic affection, but mainly fatty liver, in the general population. Here, we demonstrate the impact of the PNPLA3 polymorphism on living related donor liver transplantation (LRDLT) recipients' new onset diabetes mellitus and obesity. MethodsGenotyping of PNPLA3 rs738409 variants was analyzed using an allele discrimination assay with real-time PCR in 158 LRDLT donors and their recipients, who had no history of diabetes mellitus or fatty liver disease before transplantation and survived >1 year after transplantation. The LRDLT recipients were assessed for the development of new onset diabetes and the risk of obesity 1 year after transplantation. ResultsRecipients' PNPLA3 genotypes were associated with the development of new onset diabetes mellitus after liver transplantation (CC genotype 18.8%, CG genotype 39.1%, GG genotype 42.2%, P = 0.000; GG genotype: odds ratio 24, (95% CI 8.1–70.5). Logistic regression for the predictors of new onset diabetes showed significant risk for recipients with the PNPLA3 CG genotype (P = 0.000, OR 5.5, 95% CI 2.4–12.7) and the GG genotype (P = 0.000, OR 32, 95% CI 9–116.7). In recipients, the GG genotype enhanced the incidence of obesity, with an odds ratio of 3.8 (95% CI 1.6–8.9). The PNPLA3 gene of variants of donors did not show any significant variations with different parameters. ConclusionThe PNPLA3 L148M (rs738409) polymorphism of recipients, not donors carries a risk for new onset diabetes and obesity in LRDLT recipients post-transplant. That means there is a peripheral effect, rather than a central effect, of genotype.

Association Between PNPLA3 rs738409 C>G Variant and Liver-Related Outcomes in Patients With Nonalcoholic Fatty Liver Disease

Patients with nonalcoholic fatty liver disease (NAFLD) have an increased risk for liver-related complications, such as decompensation, hepatocellular carcinoma (HCC), and death; the severity of liver fibrosis and metabolic comorbidities are the main risk factors. A single nucleotide polymorphism in patatin-like phospholipase domain-containing-3 (PNPLA3) gene is associated with higher prevalence of liver damage and HCC, but there are no data from prospective studies of outcomes of patients with this polymorphism. We investigated whether the common rs738409 variant in PNPLA3 gene associates with the occurrence of liver-related events and death in a large cohort of patients with NAFLD. We followed 471 consecutive individuals at a hospital in Italy with a diagnosis of NAFLD based on histologic factors or a diagnosis of compensated NAFLD-related cirrhosis based on clinical factors for at least 6 months, from March 2004 through December 2018. We collected data on the occurrence of hepatic and extrahepatic outcomes, including decompensation and HCC, cardiovascular events and extrahepatic cancers, and overall and liver-related death. We detected the rs738409 G>C polymorphism in DNA from patient blood samples using the TaqMan assay. During a median follow-up time of 64.6 months (range 6.1-175 months) 26 cases of decompensation, 13 HCCs, and 16 deaths (12 liver-related) were recorded. All liver-related events, including liver-related death, occurred in patients with F3 fibrosis or cirrhosis. The prevalence of PNPLA3 rs738409 GG, GT, and TT genotypes was 31.8%, 45.6%, and 22.6%, respectively. After adjusting for clinical, metabolic, and histologic risk factors, PNPLA3 C>G variant was associated with a higher risk of decompensation (hazard ratio [HR], 2.10; 95% CI, 1.03-4.29; P = .04), HCC (HR, 2.68; 95% CI, 1.01-7.26; P = .04), and liver-related death (HR, 3.64; 95% CI, 1.18-11.2; P=.02) by multivariate Cox regression analysis. In the subgroup of 162 patients with F3 fibrosis or cirrhosis, we confirmed the independent association between the PNPLA3 variant and decompensation (HR, 2.00; 95% CI, 1.01-3.97; P = .04), HCC (HR, 2.66; 95% CI, 1.02-7.13; P=.04), and liver-related death (HR, 3.64, 95% CI, 1.18-11.2; P = .02). We found no association between PNPLA3 genotype and cardiovascular events, extrahepatic cancers, or overall mortality. Patients with NAFLD carrying PNPLA3 rs738409 G>C variant are at higher risk of liver-related events and death.

The PNPLA3 rs738409 C>G variant influences the association between low skeletal muscle mass and NAFLD: the Shanghai Changfeng Study.

Age-related skeletal muscle loss and patatin-like phospholipase domain-containing 3 (PNPLA3) polymorphisms are both associated with increased liver steatosis and fibrosis in the absence of obesity. To investigate the influence of PNPLA3 polymorphism on the relationship between skeletal muscle loss and non-alcoholic fatty liver disease (NAFLD). Liver fat content was measured using a quantitative ultrasound method, and liver fibrosis was assessed by NAFLD fibrosis, BARD and FIB-4 scores in 3969 Chinese adults. The degree of sarcopenia was measured by weight-adjusted appendicular skeletal muscle mass (ASM%=appendicular skeletal muscle mass(kg)/body weight(kg)100%). The NAFLD proportion increased from 19.9% to 41.2% in men and 26.3% to 42.3% in women with decreasing ASM% quartiles (P<0.001). Low ASM% was inversely associated with NAFLD in PNPLA3 CC (odds ratio [OR]: men, 0.735 [0.610-0.885] and women, 0.812 [0.718-0.918], both P=0.001) and CG (OR: men, 0.673 [0.573-0.790] and women, 0.798 [0.713-0.893], both P<0.001) but not GG genotype carriers. The association remained significant after adjustment for age, cigarette smoking, fat mass, interaction between fat mass and ASM%, obesity, diabetes and all components of metabolic syndrome. Subgroup analyses found that PNPLA3 GG gene variant did not increase the risk for NAFLD in individuals with low ASM% regardless of obesity status. Low ASM% also increased risk for liver fibrosis (all P<0.05), which became insignificant after multiple adjustments. Low ASM% is associated with NAFLD and liver fibrosis. Dissociation of sarcopenia and NAFLD was found in PNPLA3 GG genotype carriers. A stratification based on PNPLA3 genotypes might facilitate personalised treatment for NAFLD.

Validation of PNPLA3 polymorphisms as risk factor for NAFLD and liver fibrosis in an admixed population

Introduction and aimStudies have shown that two polymorphisms were associated with steatosis and progression of non-alcoholic fatty liver disease (NAFLD) in different populations: the Patatin-like Phospholipase Domain Containing 3 (PNPLA3) and Transmembrane 6 Superfamily Member 2 (TM6SF2). However, the frequency and significance of these polymorphisms in an admixed population, i.e., Brazilian, is unknown. Therefore, we aimed to evaluate them in healthy subjects in comparison to patients with NAFLD. Material and methodsThis was a multicenter cross-sectional study in 248 patients with biopsy-proven NAFLD and in 134 healthy controls from two tertiary centers in Brazil. PNPLA3 (rs738409 c.444C>G) and TM6SF2 (rs58542926 c.449C>T) polymorphisms were evaluated. ResultsIn controls, the frequencies of PNPLA3 CC and CG+GG were 49.25% and 50.74%, respectively; in NAFLD patients, this was 31.05% and 68.88% (p=0.0044, 95% CI 1.037–2.977). PNPLA3 GG subjects had an increased risk (3.29-fold) of having NAFLD when compared to CC subjects (p=0.0044, 95% CI 1.504–7.225). In patients with nonalcoholic steatohepatitis (NASH), PNPLA3 GG compared to CC was associated with higher AST levels [38.4±25.3 versus 36.7±40.1IU/L, p=0.0395)] and with the presence of liver fibrosis (≥F2 fibrosis, p=0.0272). TM6SF2 polymorphisms were not in Hardy-Weinberg equilibrium in our NAFLD group precluding further analysis. ConclusionWe demonstrated for the first time that PNPLA3 CG+GG increase the risk of NAFLD among Brazilian subjects. Moreover, PNPLA3 GG was associated with liver enzyme elevation and fibrosis in NASH patients.

Association between PNPLA3 rs738409 polymorphism and nonalcoholic fatty liver disease (NAFLD) susceptibility and severity: A meta-analysis.

Objective:This meta-analysis is to investigate the relationship between the patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 polymorphism and the susceptibility and severity of nonalcoholic fatty liver disease (NAFLD).Methods:Chinese Journal Full-text Database, Wanfang Database, VIP Database, and PubMed Database were subjected to case-control study retrieving, from January 2008 to December 2014. Following key words were used: fatty liver, PNPLA3, and rs738409 gene or variants or polymorphism or alleles. Meta-analysis was performed based on the retrieved articles.Results:In total 65 studies were first retrieved according to the key words, and finally 21 studies with 14,266 subjects were included. Meta-analysis showed that PNPLA3 rs738409 polymorphism exerted strong influence not only on fatty liver but also on the histological injury. PNPLA3 rs738409 [G] allele was a risk factor for NAFLD (GG vs CC, OR = 4.01, 95% CI 2.93–5.49; GC vs CC, OR = 1.88, 95% CI 1.58–2.24). PNPLA3 gene variant was significantly associated with the increased serum alanine aminotransferase (ALT) levels (GG vs CC, standardized mean difference = 0.47, 95% CI 0.14–0.81). In addition, nonalcoholic steatohepatitis (NASH) was more frequently observed in G allele carriers (GG vs CC, OR = 3.24, 95% CI 2.79–3.76; GC vs CC, OR = 2.14, 95% CI 1.43–3.19).Conclusion:PNPLA3 rs738409 polymorphism is not only a factor significantly associated with the susceptibility of NAFLD, but also related to the susceptibility of aggressive diseases.

Patatin-like phospholipase domain containing 3 variants differentially impact metabolic traits in individuals at high risk for cardiovascular events.

Single nucleotide polymorphism (SNP) rs738409 C>G in the patatin‐like phospholipase domain containing 3 (PNPLA3) gene results in an amino acid exchange from isoleucin to methionine at position I148M of PNPLA3. The expression of this loss‐of‐function mutation leads to impaired hepatocellular triglyceride hydrolysis and is associated with the development of liver steatosis, fibrosis, and hepatocellular carcinoma. In contrast to these well‐established associations, the relationship of the PNPLA3 rs738409 variant with other metabolic traits is incompletely understood. We therefore assessed the association of the PNPLA3 rs738409 genotype with relevant metabolic traits in a prospective study of patients at high risk for cardiovascular events, i.e., patients undergoing coronary angiography. In a total of 270 patients, known associations of the PNPLA3 rs738409 GG genotype with nonalcoholic steatohepatitis and liver fibrosis were confirmed. In addition, we found an association of the PNPLA3 rs738409 G allele with the presence of diabetes (22% versus 28% versus 58% for CC versus CG versus GG genotype, respectively; P = 0.02). In contrast to its association with nonalcoholic fatty liver disease, liver fibrosis, and diabetes, the minor G allele of PNPLA3 rs738409 was inversely associated with total serum cholesterol and low‐density lipoprotein serum levels (P = 0.003 and P = 0.02, respectively). Finally, there was a trend toward an inverse association between the presence of the PNPLA3 rs738409 G allele and significant coronary heart disease. Comparable trends were observed for the transmembrane 6 superfamily member 2 (TM6SF2) 167 K variant, but the sample size was too small to evaluate this rarer variant. Conclusion: The PNPLA3 rs738409 G allele is associated with liver disease but also with a relatively benign cardiovascular risk profile. (Hepatology Communications 2018;2:798‐806)

The rs4686434 variant in the fetuin B (FETUB) locus is associated with intrahepatic triglyceride content in obese Chinese adults.

This study explored associations of genetic variants in the fetuin B (FETUB) locus with intrahepatic triglyceride (IHTG) content. Four tagging single-nucleotide polymorphisms (SNPs) of the FETUB locus and patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 and transmembrane 6 super family member 2 (TM6SF2) rs58542926 were genotyped in 418 obese Chinese adults in whom serum FETUB and IHTG were measured. Subjects carrying the minor G allele for FETUB rs4686434 (AG/GG) had lower serum FETUB levels (mean [±SD] 3.89 ± 1.36 vs 4.22 ± 1.46 μg/mL; P = 0.021) and IHTG content (12.7 ± 9.4% vs 14.6 ± 9.8%; P = 0.045) than their controls (AA), whereas IHTG content was higher in those carrying the minor G allele for PNPLA3 rs738409 (CG/GG) than in their controls (CC; 14.5 ± 10.1% vs 12.0 ± 8.6%; P = 0.012). After adjusting for potential confounders, IHTG content was lower in carriers of the minor G allele for FETUB rs4686434 (AG/GG vs AA, β -2.27 ± 0.91, P = 0.012), but was higher in carriers of the minor G allele for PNPLA3 rs738409 (CG/GG vs CC, β 2.65 ± 0.97, P = 0.006). There was a significant joint effect between FETUB rs4686434 and PNPLA3 rs738409 on IHTG content, with increasing genetic risk score (counting the risk allele of A in rs4686434 and G in rs738409) being associated with higher IHTG content (β 1.85 ± 0.48, P <0.001). Carrying the minor G allele for FETUB rs4686434 was significantly associated with decreased IHTG content and may affect hepatic triglyceride accumulation in individuals at high risk of non-alcoholic fatty liver disease.

PNPLA3 rs738409 polymorphism is associated with liver fibrosis progression in patients with chronic hepatitis C: A repeated measures study

BackgroundHost genetic background has been associated with liver fibrosis progression. ObjectiveTo analyze the association between the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 polymorphism and liver fibrosis progression in hepatitis C virus (HCV)-infected patients. Study designIn this retrospective cohort study, 187 patients with chronic HCV infection were included, who had at least two liver stiffness measurements (LSM) by transient elastography during the follow-up. Results were expressed in kilopascals (kPa). The analysis of genetic association was carried out according to additive model by using Generalized Linear Models. ResultsNo patients had advanced fibrosis/cirrhosis at baseline. During a median follow-up time of 47.9 months, 15 patients developed advanced fibrosis and 17 cirrhosis. In multivariate analysis adjusted by the main clinical and epidemiological covariates, the rs738409 G allele was related to higher increase of LSM values during the follow-up (adjusted arithmetic mean ratio (aAMR) = 1.16 (95%CI = 1.04; 1.29); p = .006) and higher odds of having progression to advanced fibrosis [aOR = 2.03 (95%CI = 1.01; 4.06); p = .045], and progression to cirrhosis [aOR = 3.03 (95%CI = 1.26; 7.30); p = .014]. ConclusionsPNPLA3 rs738409 polymorphism appears to be related to the increased progression of liver fibrosis in HCV infected patients.

Association between PNPLA3 (rs738409 C>G) variant and hepatocellular carcinoma in Asian chronic hepatitis C patients: A longitudinal study.

Prdevious meta-analyses assess whether or not patatin-like phospholipase domain containing 3 (PNPLA3) (rs738409C>G) was associated with increased risk of hepatocellular carcinoma (HCC) in Caucasians patients with hepatitis C virus (HCV)-related cirrhosis, these meta-analyses did not provide firm conclusions. Only one cross-sectional study involving Asian patients has previously been conducted to explore this issue. We aim to investigate this in a longitudinal cohort of Asian chronic hepatitis C (CHC) patients. We consecutively enrolled 1011 CHC patients who underwent liver biopsy before initiating interferon-based therapy. These patients were followed-up and screened for HCC up to a median of 6.9 years. The influence of rs738409 (GG) genotype on the occurrence of HCC was assessed using the Kaplan-Meier method, then according to the multivariate Cox model. During follow-up, 143 (14.1%) patients developed HCC. rs738409 (GG) genotype was not associated with time-to-HCC development on multivariate Cox regression (P=0.634). When considering the occurrence of these events over time, rs738409 (GG) genotype did not influence the risk of HCC development (log-rank=0.12). Among 261 patients with liver cirrhosis, rs738409 (GG) genotype was not associated with time-to-HCC development on multivariate Cox regression (P=0.737). When considering the occurrence of these events over time, rs738409 (GG) genotype did not influence the risk of HCC development (log-rank=0.72). In this longitudinal study with liver biopsy to stage liver fibrosis, we affirm there is no influence of the rs738409 (GG) genotype on the occurrence of HCC in Asian CHC patients, including cirrhotic patients.

Childhood factors in the development of health anxiety: A systematic review

Host genetic background has been associated with liver fibrosis progression.To analyze the association between the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 polymorphism and liver fibrosis progression in hepatitis C virus (HCV)-infected patients.In this retrospective cohort study, 187 patients with chronic HCV infection were included, who had at least two liver stiffness measurements (LSM) by transient elastography during the follow-up. Results were expressed in kilopascals (kPa). The analysis of genetic association was carried out according to additive model by using Generalized Linear Models.No patients had advanced fibrosis/cirrhosis at baseline. During a median follow-up time of 47.9 months, 15 patients developed advanced fibrosis and 17 cirrhosis. In multivariate analysis adjusted by the main clinical and epidemiological covariates, the rs738409 G allele was related to higher increase of LSM values during the follow-up (adjusted arithmetic mean ratio (aAMR) = 1.16 (95%CI = 1.04; 1.29); p = .006) and higher odds of having progression to advanced fibrosis [aOR = 2.03 (95%CI = 1.01; 4.06); p = .045], and progression to cirrhosis [aOR = 3.03 (95%CI = 1.26; 7.30); p = .014].PNPLA3 rs738409 polymorphism appears to be related to the increased progression of liver fibrosis in HCV infected patients.

Development of hepatocellular carcinoma in Japanese patients with biopsy-proven non-alcoholic fatty liver disease: Association between PNPLA3 genotype and hepatocarcinogenesis/fibrosis progression.

Some patients with non-alcoholic fatty liver disease (NAFLD) develop hepatocellular carcinoma (HCC). Patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 (encoding the I148M variant) has been associated with advanced fibrosis and HCC. We determined the risk factors for HCC, including the PNPLA3 rs738409 polymorphism, in Japanese patients with biopsy-proven NAFLD. In this retrospective cohort study, we analyzed hepatocarcinogenesis in 238 patients. PNPLA3 rs738409 genotype was determined by allelic discrimination in 130 patients. Among them, 86 patients who were followed up for >5years and without liver cirrhosis were analyzed to clarify the relationship between PNPLA3 genotype and long-term changes in biomarkers. Of 238 patients, PNPLA3 genotype frequencies were: CC, 0.14; CG, 0.46; and GG, 0.40. During a follow-up period of 6.1years, 10 patients (4.2%) with non-alcoholic steatohepatitis developed HCC. The cumulative rate of HCC was 1.9% at the end of the 5th year and 8.3% at the end of the 10th year. Multivariate analysis identified PNPLA3 genotype GG (hazard ratio, 6.36; P = 0.019) and fibrosis stage (fibrosis stage 3/4; hazard ratio, 24.4; P = 0.011) as predictors of HCC development. In the long follow-up cohort, a larger reduction in platelet count was found in the GG group (P = 0.032) despite a larger reduction in alanine aminotransferase (P = 0.023) compared to that in the CC/CG group. In Japanese patients with NAFLD, severe fibrosis and PNPLA3 GG genotype were predictors of HCC development, independent of other known risk factors. Patients with the PNPLA3 GG genotype have the potential for a decreased platelet count, even when alanine aminotransferase levels are well controlled.

The PNPLA3 rs738409 C > G polymorphism is associated with the risk of progression to cirrhosis in NAFLD patients

Background and aims: The patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 C > G single nucleotide polymorphism (SNP) has been associated with steatosis and fibrosis in previous NAFLD populations in which cirrhotic patients were very poorly represented. Since not all NAFLD with fibrosis evolve to cirrhosis, we investigated the specific risk of cirrhosis conferred in NAFLD patients by carrying this SNP. Methods: Three groups were studied: patients with NASH-cirrhosis; patients with biopsy-proven non-cirrhotic NAFLD; healthy subjects undergoing medicine check-ups. Epidemiological, anthropometric, and clinical data were collected, and the SNP was analyzed by pyrosequencing. Results: Sixty-one patients with NASH-cirrhosis, 60 with non-cirrhotic NAFLD, and 125 healthy controls were included. Frequency of the PNPLA3 minor (G) allele was increased in patients with NASH-cirrhosis compared with non-cirrhotic NAFLD and controls (allele frequency: 0.598 versus 0.367 versus 0.2, respectively, p < 0.001), and different between the latter two groups (p < 0.001). Three-quarters (74%) of NASH cirrhotics carried at least one G allele, and almost half of them (46%) were GG homozygous. By multivariate analysis in the NAFLD population, each copy of the G allele was associated with an almost doubling of the risk of cirrhosis [OR 1.8 (1.02–3.2)], while being GG homozygous with a tripled risk compared with being CC homozygous [3.01 (1.03–10.8)]. Conclusions: In NAFLD patients, carriage of the PNPLA3G allele, and particularly of the GG genotype, is significantly associated with the risk of cirrhotic evolution. If confirmed in larger series, these results would suggest that most of NASH cases require the contribution of an altered PNPLA3 function to progress until cirrhosis.

PNPLA3 genetic variants determine hepatic steatosis in non-obese chronic hepatitis C patients.

The influence of patatin-like phospholipase domain-containing 3 (PNPLA3) genetic variants in the development of liver steatosis in Asian chronic hepatitis C patients remains elusive. A total of 1018 biopsy-proven chronic hepatitis C patients were enrolled for evaluation. The proportions of PNPLA3 rs738409 GG genotype carriage were 7.8% (44/563), 15.8% (58/367) and 19.3% (17/88) in patients with no (liver fat content <5%), mild (5–33%) and moderate/severe (>66%) hepatic steatosis, respectively (trend P < 0.001). Stepwise logistic regression analysis revealed that the strongest factor independently associated with steatosis was the carriage of the PNPLA3 rs738409 GG genotype (odds ratio [OR]/95% confidence intervals [CI]:2.34/1.557–3.515, P < 0.001). Among the patients with BMI < 24 kg/m2, carriage of the rs738409 GG genotype was the only factor associated with hepatic steatosis (OR/CI:3.44/1.824–6.500, P < 0.001). PNPLA3 genetic variants had minimal effects on hepatic steatosis among overweight or obese patients. Compared to patients with BMI<24 kg/m2/non-GG genotype, those with BMI>24 kg/m2/GG genotype were more likely to have hepatic steatosis (OR/CI:3.87/2.292–6.524, P < 0.001). In conclusions, both PNPLA3 genetic variants and BMI played important roles in hepatic steatosis among Asian chronic hepatitis C patients. However, the genetic effect was mainly restricted to non-obese patients.

Impact of IL28B and PNPLA3 polymorphisms on treatment outcomes in patients infected with genotype 6 hepatitis C virus.

Interleukin-28B (IL28B) and patatin-like phospholipase domain containing 3 (PNPLA3) gene polymorphisms are associated with hepatitis C virus (HCV) clearance and fatty liver, respectively. We aimed to test if their polymorphisms are associated with virologic responses in Chinese chronic hepatitis C (CHC) patients. This was a retrospective-prospective cohort study. Consecutive patients infected by genotype 1 and 6 HCV received antiviral therapy were included. Host IL-28B rs12979860/rs8099917 and PNPLA3 rs738409 genotype were tested. The primary outcome was sustained virologic response (sustained virologic response [SVR]: undetectable HCV RNA 24 weeks post-treatment). From 305 patients had positive antibody to HCV, 52 and 31 patients infected by genotype 1 and 6 HCV, respectively were recruited. Mean age was 58 ± 11 years; 70% were male. Mean baseline HCV RNA was 6.8 ± 2.7 log IU/ml. The SVR for patients infected by genotype 1 and 6 HCV was 67.3% and 90.3%, respectively. The proportions of IL28B genotypes were 78%, 21%, and 1% for TT/TG/GG at rs8099917, and 81%, 18%, and 1% for CC/TC/TT at rs12979860, respectively. The proportions of PNPLA3 rs738409 genotypes were 16%, 36%, and 48% for GG/GC/CC. IL28B genotype was significantly associated with SVR in patients infected by genotype 1 but not genotype 6 HCV, with 80% versus 38% of patients infected by genotype 1 achieved SVR carried TT versus TG/GG at rs8099917, respectively (P=0.003). PNPLA3 genotype was not associated with SVR. IL28B gene with rs8099917 T allele as an independent predictor of SVR in Chinese CHC patients infected by genotype 1 but not genotype 6 HCV.