Abstract
Background
Nonalcoholic fatty liver disease (NAFLD) is a significant contributor to global hepatic disorders. ADIPOQ gene single‐nucleotide polymorphisms have been associated with NAFLD susceptibility, but with inconsistent results across the studies. This study aimed to investigate the association between ADIPOQ polymorphisms (+276G>T, rs1501299 and −11377C>G, rs266729) and the risk of NAFLD.
Methods
PubMed, Embase, Wanfang, Web of Science, and China National Knowledge Infrastructure databases were used to identify the relevant published literature. Statistical analyses were calculated with STATA 11.0 software and RevMan 5.2. Summary odds ratios (OR) and 95% confidence intervals (CIs) were generated to assess the strength of the associations.
Results
Eleven relevant articles with a total of 3,644 participants (1,847 cases/1,797 controls) were included. Our meta‐analysis results revealed that ADIPOQ gene +276G>T polymorphism was not associated with NAFLD under various genetic models (allele model: OR = 0.99, 95% CI [0.69, 1.41]; dominant model: OR = 1.06, 95% CI [0.71, 1.58]; recessive model: OR = 0.83, 95% CI [0.42, 1.65]; homozygous model: OR = 0.86, 95% CI [0.38, 1.95]; heterozygous model: OR = 1.10, 95% CI [0.80, 1.53]; respectively). Moreover, no statistical significant association was found between +276G>T and NAFLD risk in the subgroups. ADIPOQ gene −11377C>G polymorphism significantly increased the risk of NAFLD (allele model: OR = 1.49, 95% CI [1.28, 1.75]; dominant model: OR = 1.64, 95% CI [1.35, 1.99]; recessive model: OR = 1.77, 95% CI [1.16, 2.70]; homozygous model: OR = 2.13, 95% CI [1.38, 3.28]; heterozygous model: OR = 1.58, 95% CI [1.29, 1.93]; respectively).
Conclusion
ADIPOQ gene −11377C>G may be a risk factor for NAFLD, while there was no association between ADIPOQ gene +276G>T polymorphism and the risk of NAFLD. Further studies are needed to detect the relationship between these ADIPOQ polymorphisms and NAFLD.
Keywords: adiponectin gene, ADIPOQ, meta‐analysis, metabolism syndrome, non‐alcoholic fatty liver disease, polymorphism
1. INTRODUCTION
Nonalcoholic fatty liver (NAFLD) is one of the most common chronic liver diseases worldwide (Chalasani et al., 2018; Younossi et al., 2016). NAFLD is a prevalent metabolic liver disease, which is on the rise in the world (Bugianesi et al., 2002; Dyson et al., 2014). Up to one‐fifth of NAFLD patients will develop nonalcoholic steatohepatitis, which may further develop into liver fibrosis, cirrhosis and complications, including hepatocellular carcinoma (Charlton et al., 2011; Kacso, Trifa, Popp, & Kacso, 2012). Little is known about the underlying mechanism for the development and progress of NAFLD, however, it is a complex metabolic state in which both lifestyle and genetic factors are pathogenic factors.
ADIPOQ (OMIM: 605441) is a kind of adipose tissue specific cytokine secreted mainly by white adipose tissue, which plays an important role in regulating insulin sensitivity, glucose homeostasis and lipid metabolism (Bessone, Razori, & Roma, 2019; Fu, 2014). NAFLD is the main liver manifestation of metabolic syndrome (Marchesini et al., 1999; Socha et al., 2007; Yki‐Jarvinen, 2014). Not only is insulin resistance an independent risk factor for NAFLD severity, but obesity, Type 2 diabetes, dyslipidemia and hypertension are also major causes of NAFLD (Cai et al., 2005; Lindenmeyer & McCullough, 2018; Wong et al., 2008). Therefore, we hypothesized that the gene coding for ADIPOQ, adiponectin, also known as AMP1 gene, located on chromosome 3q27, which is the susceptible locus for NAFLD. To date, in diverse populations, massive studies have explored the relationship between ADIPOQ gene single‐nucleotide polymorphisms (SNPs) and NAFLD risk, as rs1501299 and 266729 (Stefan, Haring, & Cusi, 2018). However, the results of these studies have been inconsistent, may be due to sample sizes, diverse ethnicity and so on. Therefore, we conducted a meta‐analysis to detect the associations between two ADIPOQ gene polymorphisms and NAFLD risk by previous studies.
2. MATERIALS AND METHODS
2.1. Literature search strategy
We used PubMed, Embase, Wanfang, Web of Science, and China National Knowledge Infrastructure databases to search for potentially relevant studies published before November, 2018, which focused on the associations of the two polymorphisms in the ADIPOQ gene (rs1501299, rs266729) with NAFLD susceptibility without language restrictions. The search strategy was based on a combination of the following terms: adiponectin or ADIPOQ or adipose most abundant gene transcript 1 or APM1 or rs1501299 or rs266729 AND nonalcoholic fatty liver disease or NAFLD or nonalcoholic steatohepatitis AND single‐nucleotide polymorphism or genetic polymorphism. We performed a manual search of references included in pertinent articles and reviews. If there was duplication of published literature by the same research group, the study with the larger sample size was selected.
2.2. Inclusion and exclusion criteria
Potentially relevant studies in our meta‐analysis have to meet following inclusion criteria: (a) case‐control studies focused on the association between the ADIPOQ gene+276G>T (NM_001177800.1:c.214+62G>T) and −11377C>G (NG_021140.1:g.4012C>G) and NAFLD risk, (b) every patient selected have to base on diagnostic criteria for NAFLD: persistently (at least 6 months) abnormal levels of aspartate aminotransferase and alanine aminotransferase, or evidence of fatty liver using ultrasound or other imaging techniques, with a daily alcohol consumption <20 g/day in men and <10 g/day in women; patients with infectious (such as hepatitis B virus and hepatitis C virus and HIV), viral, drug‐induced, auto‐immune hepatitis, and other serious diseases (including severe heart, lung, brain, or kidney diseases) were excluded, (c) the genotype distribution in control group should accord with Hardy–Weinberg equilibrium (HWE), (d) published data of allele and genotype frequencies must be explicit or could be calculated from the article text. Excluded articles should have the following characteristics: (a) case‐control studies without control information, (b) existing duplicate publication of data, (c) not enough data information form articles.
2.3. Data extraction
Original data from published studies were independently extracted by two investigators into a standardized form. Contested issues in data extraction were resolved through discussions and re‐inspection with the third investigator. The following information was collected: the first author's surname, year of publication, country, ethnicity, source of controls, number of cases and controls, genotyping methods, frequency of allele and genotype, HWE and Newcastle–Ottawa Scale (NOS) score.
2.4. Quality assessment
The methodological quality of each literature included in our analysis was estimated using the NOS, which scores of 1–3, 4–6 and 7–9 meaning low‐, intermediate‐, and high quality studies respectively in this meta‐analysis. Two authors independently evaluated the quality of selected articles. Differences were resolved by the third author or by discussion, until subsequent consensus was reached.
2.5. Statistical analysis
Summary odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to quantitatively assess the association between ADIPOQ SNPs and NAFLD risk under five comparison models: the allele model, dominant model, recessive model, homozygous model, and heterozygous model. HWE in the control group was tested by chi‐square test (χ2‐test) for studies included in the current meta‐analysis. Z‐test was applied to examine the statistical significance of the pooled OR. Among‐studies heterogeneity was assessed using Cochran's Q‐test and I 2‐test. When I 2 > 50% or p < 0.05, the heterogeneity was deemed as significant, we selected the random‐effect model to calculate pooled ORs, on the contrary, the fixed‐effect mode was performed. Sensitivity analysis was performed by removing each individual studies sequentially or by deleting the outliers to assess the stability of the results. Begg's funnel plots were conducted to assess the significance of publication bias, and Egger's test was further supplemented (p < 0.05 was considered representation of statistically significant publication bias). Meta‐analysis was conducted using the Cochrane Collaboration RevMan 5.2 and Stata 11.0 software (Stata Corporation, College Station, TX).
3. RESULTS
3.1. Characteristics of the studies included
The search strategy retrieved 126 potentially relevant studies, by browsing the title and abstract, a total of 107 articles were excluded. Then two other articles were removed because of repeated publications. Three articles were excluded because of a lack of detailed genotype distribution information. Three articles were excluded due to distributions of genotypes in controls were not consistent with the HWE. Ultimately, we included eleven articles (Cheng, Jiang, Xin, An, & Xuan, 2015; Hashemi et al., 2013; He, Xu, Han, Chen, & Chen, 2017; Li, Li, Zhang, Zhong, & Shi, 2015; Mohseni, Moghbelinejad, & Najafipour, 2017; Musso et al., 2008; Tokushige et al., 2009; Wang et al., 2008; Wei, Li‐Qun, Xiao‐Ling, Jian, & Guo‐Yue, 2016; Ye, Yu, Wang, & Lu, 2014; Zhou et al., 2010), involving 1,847 cases and 1,797 controls in present meta‐analysis. The study selection outlined is shown in Figure 1. The characteristics of main studies are summarized in Table 1. There were 10 studies for ADIPOQ +276G>T, the features of these ten articles: nine studies focused on Asian ethnicities and one study was Caucasian populations, besides one study (Gong et al., 2013) that does not conform to HWE. So there are nine articles that meet the inclusion criteria finally. For −11377C>G polymorphism, six relevant studies were included in Table 1, among them, due to two studies (Gupta et al., 2012; Zhang, Guo, Qin, & Li, 2016) of the distribution of genotypes in controls were not consistent with the HWE. So, eligible studies were four on this related topic.
Figure 1.

Flow diagram of the study search and selection process. NAFLD: nonalcoholic fatty liver disease
Table 1.
Main characteristics of all eligible studies
| First author (year) | Country | Ethnicity | Source of controls | Sample size (case/control) | Genotyping method | Case (genotype) | Control (genotype) | HWEa | NOS score | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GG | GT | TT | GG | GT | TT | ||||||||
| rs1501299 | |||||||||||||
| Musso et al. (2008) | Italy | Caucasian | PB | 70/70 | PCR‐RFLP | 17 | 51 | 2 | 38 | 29 | 3 | 0.381 | 9 |
| Hashemi et al. (2013) | Iran | Asian | PB | 83/93 | Tetra ARMS‐PCR | 42 | 39 | 2 | 53 | 38 | 2 | 0.104 | 9 |
| He et al. (2017) | Chinese | Asian | HB | 102/100 | PCR‐RFLP | 49 | 36 | 17 | 20 | 39 | 41 | 0.066 | 7 |
| Li et al. (2015) | Chinese | Asian | HB | 357/357 | PCR‐RFLP | 113 | 164 | 80 | 161 | 165 | 31 | 0.215 | 7 |
| Mohseni et al. (2017) | Iran | Asian | PB | 75/76 | PCR‐sanger sequencing | 33 | 32 | 10 | 39 | 28 | 9 | 0.268 | 8 |
| Tokushige et al. (2009) | Japan | Asian | PB | 119/115 | AS‐PCR | 67 | 47 | 4 | 59 | 47 | 9 | 0.932 | 9 |
| Zhou et al. (2010) | Chinese | Asian | PB | 106/106 | PCR‐RFLP | 68 | 29 | 9 | 50 | 39 | 17 | 0.057 | 7 |
| Wang et al. (2008) | Chinese | Asian | HB | 165/160 | PCR‐RFLP | 74 | 82 | 9 | 74 | 73 | 13 | 0.392 | 9 |
| Zhang et al. (2016) | Chinese | Asian | HB | 302/310 | PCR‐RFLP | 161 | 120 | 21 | 184 | 112 | 14 | 0.557 | 7 |
| Gong et al. (2013) | Chinese | Asian | PB | 255/405 | PCR‐RFLP | 155 | 75 | 25 | 201 | 153 | 51 | 0.012 | 6 |
| CC | CG | GG | CC | CG | GG | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| rs266729 | |||||||||||||
| Gupta et al. (2012) | India | Asian | HB | 137/250 | PCR | 77 | 53 | 7 | 156 | 92 | 2 | 0.003 | 7 |
| Cheng et al. (2015) | Chinese | Asian | HB | 338/280 | PCR‐sanger sequencing | 158 | 149 | 31 | 164 | 102 | 14 | 0.715 | 8 |
| Hashemi et al. (2013) | Iran | Asian | PB | 83/93 | Tetra ARMS‐PCR | 27 | 53 | 3 | 49 | 41 | 3 | 0.107 | 8 |
| Ye et al. (2014) | Chinese | Asian | HB | 130/130 | PCR‐RFLP | 77 | 47 | 6 | 83 | 40 | 7 | 0.458 | 7 |
| Zhang et al. (2016) | Chinese | Asian | HB | 200/200 | PCR‐RFLP | 57 | 69 | 74 | 143 | 28 | 29 | 0 | 7 |
| Zhang et al. (2016) | Chinese | Asian | HB | 302/310 | PCR‐RFLP | 152 | 126 | 24 | 197 | 102 | 11 | 0.619 | 7 |
HB: hospital‐based; PB: population‐based; AS: allele‐specific; PCR‐RFLP: polymerase chain reaction restriction fragment length polymorphism; NOS: Newcastle–Ottawa Scale; ARMS‐PCR: amplification refractory mutation system; HWE: Hardy–Weinberg Equilibrium.
The numbers in bold values indicate that the genotype distribution of control group in certain studies do not accord with Hardy‐Weinberg equilibrium.
p value for HWE test in controls.
3.2. Associations between +276G>T (rs1501299) polymorphism and NAFLD
We included nine articles published on the association between +276G>T polymorphism and NAFLD risk. We found that no significant associations between this polymorphism and NAFLD risk (alleles model: OR = 0.99, 95% CI [0.69, 1.41]; dominant model: OR = 1.06, 95% CI [0.71, 1.58]; recessive model: OR = 0.83, 95% CI [0.42, 1.65]; homozygous model: OR = 0.86, 95% CI [0.38, 1.95]; heterozygous: OR = 1.10, 95% CI [0.80, 1.53], respectively, Table 2) based on combined results from all studies. Yet significant heterogeneity was observed in overall comparisons. To estimate the source of heterogeneity, we performed sensitivity analyses though omitting each individual study in turn. For recessive model, the significant heterogeneity decreased though excluded the study by Li et al. (2015), it means that this study might be a part of source of heterogeneity (Figure 2). While sensitivity analysis failed to fully explain the source of heterogeneity. So to further explore the heterogeneity of five genetic models, we adopted subgroup analysis (Table 3). Our analyses showed that no associations between +276G>T polymorphism and NAFLD risk were observed in the subgroups in five genetic models.
Table 2.
Meta‐analysis results of the associations between rs1501299 and rs266729 polymorphisms in ADIPOQ gene and non‐alcoholic fatty liver disease risk
| Genetic model | No. of studies | OR [95% CI] | p meta‐analysis | I 2 (%) | p aheterogeneity | Statistical method |
|---|---|---|---|---|---|---|
| rs1501299 | ||||||
| T vs. G | 9 | 0.99 [0.69, 1.41] | 0.94 | 89 | 0 | Random |
| GT+TT vs.GG | 9 | 1.06 [0.71, 1.58] | 0.78 | 84 | 0 | Random |
| TT vs. GT+GG | 9 | 0.83 [0.42, 1.65] | 0.6 | 82 | 0 | Random |
| TT vs. GG | 9 | 0.86 [0.38, 1.95] | 0.71 | 86 | 0 | Random |
| GT vs. GG | 9 | 1.10 [0.80, 1.53] | 0.55 | 73 | 0.0002 | Random |
| rs266729 | ||||||
| G vs. C | 4 | 1.49 [1.28, 1.75] | 0 | 0 | 0.51 | Fixed |
| CG+GG vs. CC | 4 | 1.64 [1.35, 1.99] | 0 | 0 | 0.45 | Fixed |
| GG vs. CG+CC | 4 | 1.77 [1.16, 2.70] | 0.009 | 0 | 0.46 | Fixed |
| GG vs. CC | 4 | 2.13 [1.38, 3.28] | 0.0006 | 0 | 0.44 | Fixed |
| CG vs. CC | 4 | 1.58 [1.29, 1.93] | 0.0001 | 0 | 0.51 | Fixed |
OR: odd ratio; CI: confidence interval.
p value for between‐study heterogeneity based on Q test.
Figure 2.

Forest plot for rs1501299 under recessive model (TT vs. GT+GG). (a) Pooled results, (b) results omitting Hong‐Jue Li et al. (2015)
Table 3.
Subgroup analysis for rs1501299 polymorphisms in ADIPOQ gene and non‐alcoholic fatty liver disease risk
| Study group | Study numbers | T vs. G | GT+TT vs. GG | TT vs. GT+GG | TT vs. GG | GT vs. GG | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| OR [95% CI] | I 2 (%)/Ph | OR [95% CI] | I 2 (%)/Ph | OR [95% CI] | I 2 (%)/Ph | OR [95% CI] | I 2 (%)/Ph | OR [95% CI] | I 2 (%)/Ph | ||
| Total | 9 | 0.99 [0.69, 1.41] | 89/0.000 | 1.06 [0.71, 1.58] | 84/0.000 | 0.83 [0.42, 1.65] | 82/0.000 | 0.86 [0.38, 1.95] | 86/0.000 | 1.10 [0.80, 1.53] | 73/0.000 |
| Enthicity | |||||||||||
| Caucasian | 1 | 1.91 [1.14, 3.18] | a | 3.70 [1.80, 7.61] | a | 0.66 [0.11, 4.06] | a | 1.49 [0.23, 9.75] | a | 3.93 [1.89, 8.17] | a |
| Asian | 8 | 0.92 [0.63, 1.34] | 89.4/0.000 | 0.93 [0.63, 1.38] | 82.4/0.000 | 0.86 [0.41, 1.75] | 84.3/0.000 | 0.82 [0.34, 1.96] | 87.9/0.000 | 0.99 [0.75, 1.32] | 62/0.01 |
| Region | |||||||||||
| Italy | 1 | 1.91 [1.14, 3.18] | a | 3.70 [1.80, 7.61] | a | 0.66 [0.11, 4.06] | a | 1.49 [0.23, 9.75] | a | 3.93 [1.89, 8.17] | a |
| Iran | 2 | 1.12 [0.86, 1.71] | 0/0.955 | 1.32 [0, 85, 2.03] | 0/0.935 | 1.14 [0.48, 2.71] | 0/0.986 | 1.30 [0.53, 3.22] | 0/0.972 | 1.32 [0.84, 2.08] | 0/0.928 |
| Chinese | 5 | 0.85 [0.49, 1.47] | 93.7/0.000 | 0.84 [0.47, 1.48] | 89.4/0.000 | 0.87 [0.33, 2.30] | 90.4/0.000 | 0.80 [0.24, 2.62] | 92.7/0.000 | 0.90 [0.60, 1.36] | 76.6/0.002 |
| Japan | 1 | 0.77 [0.51, 1.17] | a | 0.80 [0.48, 1.34] | a | 0.41 [0.12, 1.38] | a | 0.39 [0.11, 1.34] | a | 0.88 [0.52, 1.50] | a |
| Source of control | |||||||||||
| PB | 5 | 1.02 [0.67, 1.55] | 75.7/0.002 | 1.17 [0.64, 2.16] | 80.8/0.000 | 0.66 [0.39, 1.11] | 0/0.626 | 0.69 [0.37, 1.29] | 19.3/0.292 | 1.24 [0.68, 2.24] | 77.8/0.001 |
| HB | 4 | 0.95 [0.52, 1.73] | 94.2/0.000 | 0.95 [0.51, 1.74] | 89.5/0.000 | 0.99 [0.32, 3.07] | 91.9/0.000 | 0.96 [0.24, 3.74] | 93.7/0.000 | 1.01 [0.67, 1.54] | 74.6/0.008 |
| Genotyping method | |||||||||||
| PCR‐RFLP | 6 | 0.96 [0.59‐1.58] | 92.6/0.000 | 1.03 [0.59, 1.82] | 89.5/0.000 | 0.84 [0.34, 2.06] | 88.1/0.000 | 0.86 [0.29, 2.55] | 90.8/0.000 | 1.08 [0.68, 1.72] | 82.4/0.000 |
| Non‐PCR‐RFLP | 3 | 1.02 [0.75, 1.38] | 25.5/0.261 | 1.07 [0.76, 1.50] | 3.3/0.355 | 0.81 [0.40, 1.63] | 0/0.407 | 0.84 [0.37, 1.91] | 16.4/0.302 | 1.11 [0.79, 1.57] | 0/0.526 |
Notes. CI: confidence interval; OR: odds ratio; Ph: p value for heterogeneity from Q‐test; I 2: the proportion of the total variation across studies due to heterogeneity; HB: hospital‐based; PB: population‐based; PCR‐RFLP: polymerase chain reaction restriction fragment length polymorphism.
No heterogeneity was observed for only one study.
3.3. Associations between −11377C>G (rs266729) polymorphism and NAFLD
Table 2 showed the pooled results of this meta‐analysis for −11377C>G polymorphism and NAFLD involving four articles published. All participator came from Asian population. A significant association under five genetic models analysis was found (alleles model: OR = 1.49, 95% CI [1.28, 1.75]; dominant model: OR = 1.64, 95% CI [1.35, 1.99]; recessive model: OR = 1.77, 95% CI [1.16, 2.70]; homozygous model: OR = 2.13, 95% CI [1.38, 3.28]; heterozygous: OR = 1.58, 95% CI [1.29, 1.93], Table 2). Meanwhile, heterogeneity test across the four studies showed no statistical significance (I 2 = 0%, Figure 3).
Figure 3.

Forest plot represents the association between the rs266729 polymorphism and the risk of nonalcoholic fatty liver disease. (a) the homozygous model (GG vs. CC), (b) dominant model (CG+GG vs. CC)
3.4. Publication bias
Begg's funnel plot was conducted to evaluate potential publication bias among included studies. No publication bias was apparent concerning relationship between rs266729 polymorphisms and NAFLD risk, as same as rs1501299 (Figure 4).
Figure 4.

Begg's funnel plot of publication biases on the relationships between rs1501299 (a) and rs266729 (b) susceptibility with risk of non‐alcoholic fatty liver disease under dominant model. Each point represents a separate study for the indicated association. Log [OR], natural logarithm of the odds ratio, vertical line, means effect size
4. DISCUSSION
The worldwide prevalence of NAFLD is on the rise, and it is rapidly becoming the most common cause of chronic liver disease affecting 25% of the world's population (Chalasani et al., 2018; Charlton et al., 2011; Townsend & Newsome, 2016). The characteristics of metabolic syndrome (Mets) are not only very common in NAFLD patients, but also the components of Mets increase the risk of NAFLD, such as existing etiology: obesity, Type 2 diabetes, hypertension, and dyslipidemia and emerging elements: sleep apnea, colorectal cancer, osteoporosis, psoriasis, endocrinopathies, and polycystic ovary syndrome (Nasr, Ignatova, Kechagias, & Ekstedt, 2018; Stefan, Kantartzis, & Haring, 2008). The pathogenesis of NAFLD is particularly complex, since it involves interactions between genetic and environmental factors, many of which have been indistinct (Heid et al., 2006). ADIPOQ is expressed and secreted completely from adipocytes and has been identified as a cytokine with anti‐diabetes, anti‐inflammatory, and anti‐atherosclerosis properties (Fu, 2014). In addition, previous studies have demonstrated that ADIPOQ gene polymorphism may be influence plasma adiponectin concentration (Heid et al., 2006; Kadowaki et al., 2006; Maeda et al., 2001; Menzaghi et al., 2002). Significantly up‐regulated adiponectin expression in white adipose tissue leads to increased serum adiponectin concentrations (Targher et al., 2006). Low adiponectin level is closely related to the severity of liver histology, thus further supporting the hypothesis that adiponectin may be involved in the development of NAFLD (Vernon, Baranova, & Younossi, 2011). Although, several studies’ findings concerning relationship between −11377C>G and +276G>T polymorphism and NAFLD risk have been contradictory. Furthermore, previous meta‐analysis had its own limitations, we performed an updated meta‐analysis which comprehensively estimated the correlation between ADIPOQ polymorphisms and NAFLD risk. This present meta‐analysis included eligible eleven case‐control studies that were included nine studies for rs1501299 and four studies for rs266729, involving 1847 cases and 1797 controls. In general, for +276G>T polymorphism, we found that no significant association with NAFLD risk based on pooled results from all eligible studies. This conclusion might be contributed to inadequate adjustment for confounding factors, such as ethnicity, source of control, genotyping methods. By subgroup analysis, our analyses showed that no associations between this polymorphism and NAFLD risk were observed in the subgroup of country (Iran) in five genetic models, and the same result in the nonpolymerase chain reaction restriction fragment length polymorphism subgroup, no association was also detected in five genetic models. When excluded the study by Li et al. (2015), the heterogeneity drop in recessive model. Although sensitivity analysis does not explain the source of heterogeneity very well, it suggests that this particular study might be a part of a heterogeneous source. Besides, no publication bias was identified between studies, and thus we do not feel that it impacts the results.
And a significantly increased risk was discovered for relationship between −11377C>G polymorphism and NAFLD risk in different genetic models. Due to four articles focused on Asians, we make a bold assumption that among Asian population, rs266729 is a significant high‐risk factor for NAFLD. In different genetic models, a higher increased risk was found in homozygous model (GG vs. CC: OR = 2.13, 95% CI [1.38, 3.28]) than other four genetic models. As four studies focused on Asian population, further investigation involving diverse population should be studied in future analysis.
There were some limitations in this meta‐analysis. First, lack of detailed genotypic information and restrictions on inclusion criteria, so several studies have not been included in this analysis. Second, in some pooled analysis, there was significant heterogeneity, which may have unsatisfactorily explained using subgroup and sensitivity analyses. Third, our study only included relevant articles published in English or Chinese. In addition, gene‐environment interactions in relationship rs1501299 and rs266729 and NAFLD are worthy of consideration.
In conclusion, our meta‐analysis suggested that the rs1501299 polymorphism was not associated with NAFLD. The rs266729 polymorphism was found to be associated with a significant increase in NAFLD risk. However, more precise and larger studies will be expected to improve and perfect our findings.
CONFLICT OF INTEREST
The authors declare no conflict of interest.
ACKNOWLEDGMENTS
This work was supported by the National Natural Science Foundation Committee of China (Grant No. 81573240), the Liaoning Provincial Undergraduate Training Program for Innovation and Entrepreneurship of China (Grant No. 201810159184). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Liu M, Liu S, Shang M, et al. Association between ADIPOQ G276T and C11377G polymorphisms and the risk of non‐alcoholic fatty liver disease: An updated meta‐analysis. Mol Genet Genomic Med. 2019;7:e624 10.1002/mgg3.624
REFERENCES
- Bessone, F. , Razori, M. V. , & Roma, M. G. (2019). Molecular pathways of nonalcoholic fatty liver disease development and progression. Cellular and Molecular Life Sciences, 76, 99–128. 10.1007/s00018-018-2947-0 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bugianesi, E. , Leone, N. , Vanni, E. , Marchesini, G. , Brunello, F. , Carucci, P. , … Rizzetto, M. (2002). Expanding the natural history of nonalcoholic steatohepatitis: From cryptogenic cirrhosis to hepatocellular carcinoma. Gastroenterology, 123, 134–140. 10.1053/gast.2002.34168 [DOI] [PubMed] [Google Scholar]
- Cai, D. , Yuan, M. , Frantz, D. F. , Melendez, P. A. , Hansen, L. , Lee, J. , & Shoelson, S. E. (2005). Local and systemic insulin resistance resulting from hepatic activation of IKK‐beta and NF‐kappaB. Nature Medicine, 11, 183–190. 10.1038/nm1166 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chalasani, N. , Younossi, Z. , Lavine, J. E. , Charlton, M. , Cusi, K. , Rinella, M. , … Sanyal, A. J. (2018). The diagnosis and management of nonalcoholic fatty liver disease: Practice guidance from the American Association for the Study of Liver Diseases. Hepatology, 67, 328–357. 10.1002/hep.29367 [DOI] [PubMed] [Google Scholar]
- Charlton, M. R. , Burns, J. M. , Pedersen, R. A. , Watt, K. D. , Heimbach, J. K. , & Dierkhising, R. A. (2011). Frequency and outcomes of liver transplantation for nonalcoholic steatohepatitis in the United States. Gastroenterology, 141, 1249–1253. 10.1053/j.gastro.2011.06.061 [DOI] [PubMed] [Google Scholar]
- Cheng, Y. , Jiang, M. , Xin, Y. , An, B. , & Xuan, S. (2015). Association between Adiponectin polymorphisms and nonalcoholic fatty liver disease in Han Chinese population in Qingdao. The Journal of Practical Medicine, 31, 1421–1424. [Google Scholar]
- Dyson, J. , Jaques, B. , Chattopadyhay, D. , Lochan, R. , Graham, J. , Das, D. , … Reeves, H. L. (2014). Hepatocellular cancer: The impact of obesity, type 2 diabetes and a multidisciplinary team. Journal of Hepatology, 60, 110–117. 10.1016/j.jhep.2013.08.011 [DOI] [PubMed] [Google Scholar]
- Fu, Y. (2014). Adiponectin signaling and metabolic syndrome. Progress in Molecular Biology and Translational Science, 121, 293–319. 10.1016/b978-0-12-800101-1.00009-0 [DOI] [PubMed] [Google Scholar]
- Gong, L. , Li, L. , Zhao, X. , Zhang, Y. , Jiang, Y. , Gu, Y. , & Zhou, J. (2013). Association of single nucleotide polymorphisms of the adiponectin gene and plasma levels of adiponectin with risk of nonalcoholic fatty liver disease. Journal of Xinjiang Medical University, 36, 860–864 + 868. [Google Scholar]
- Gupta, A. C. , Misra, R. , Sakhuja, P. , Singh, Y. , Basir, S. F. , & Sarin, S. K. (2012). Association of adiponectin gene functional polymorphisms (−11377C/G and +45T/G) with nonalcoholic fatty liver disease. Gene, 496(1), 63–67. 10.1016/j.gene.2011.12.023 [DOI] [PubMed] [Google Scholar]
- Hashemi, M. , Hanafi Bojd, H. , Eskandari Nasab, E. , Bahari, A. , Hashemzehi, N. A. , Shafieipour, S. , … Ghavami, S. (2013). Association of adiponectin rs1501299 and rs266729 gene polymorphisms with nonalcoholic fatty liver disease. Hepatitis Monthly, 13, e9527 10.5812/hepatmon.9527 [DOI] [PMC free article] [PubMed] [Google Scholar]
- He, Z. , Xu, C. , Han, X. , Chen, Y. , & Chen, Y. (2017). Study on clinical relationships between gene polymorphism of vitamin D receptor and adiponectin with risk of nonalcoholic fatty liver disease. Chongqing Medicine, 46, 1606–1609. [Google Scholar]
- Heid, I. M. , Wagner, S. A. , Gohlke, H. , Iglseder, B. , Mueller, J. C. , Cip, P. , … Paulweber, B. (2006). Genetic architecture of the APM1 gene and its influence on adiponectin plasma levels and parameters of the metabolic syndrome in 1,727 healthy Caucasians. Diabetes, 55, 375–384. 10.2337/diabetes.55.02.06.db05-0747 [DOI] [PubMed] [Google Scholar]
- Kacso, I. M. , Trifa, A. P. , Popp, R. A. , & Kacso, G. (2012). Association of 276G>T adiponectin gene polymorphism to plasma adiponectin and albuminuria in type 2 diabetic patients. International Urology and Nephrology, 44, 1771–1777. 10.1007/s11255-011-0118-4 [DOI] [PubMed] [Google Scholar]
- Kadowaki, T. , Yamauchi, T. , Kubota, N. , Hara, K. , Ueki, K. , & Tobe, K. (2006). Adiponectin and adiponectin receptors in insulin resistance, diabetes, and the metabolic syndrome. The Journal of Clinical Investigation, 116, 1784–1792. 10.1172/jci29126 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Li, H. J. , Li, C. P. , Zhang, C. , Zhong, X. L. , & Shi, L. (2015). Association of adiponectin gene polymorphisms and nonalcoholic fatty liver disease. International Journal of Clinical and Experimental Medicine, 8, 16676–16681. [PMC free article] [PubMed] [Google Scholar]
- Lindenmeyer, C. C. , & McCullough, A. J. (2018). The natural history of nonalcoholic fatty liver disease‐an evolving view. Clinics in Liver Disease, 22(1), 11–21. 10.1016/j.cld.2017.08.003 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maeda, N. , Takahashi, M. , Funahashi, T. , Kihara, S. , Nishizawa, H. , Kishida, K. , … Matsuzawa, Y. (2001). PPARgamma ligands increase expression and plasma concentrations of adiponectin, an adipose‐derived protein. Diabetes, 50, 2094–2099. 10.2337/diabetes.50.9.2094 [DOI] [PubMed] [Google Scholar]
- Marchesini, G. , Brizi, M. , Morselli‐Labate, A. M. , Bianchi, G. , Bugianesi, E. , McCullough, A. J. , … Melchionda, N. (1999). Association of nonalcoholic fatty liver disease with insulin resistance. American Journal of Medicine, 107, 450–455. 10.1016/S0002-9343(99)00271-5 [DOI] [PubMed] [Google Scholar]
- Menzaghi, C. , Ercolino, T. , Di Paola, R. , Berg, A. H. , Warram, J. H. , Scherer, P. E. , … Doria, A. (2002). A haplotype at the adiponectin locus is associated with obesity and other features of the insulin resistance syndrome. Diabetes, 51, 2306–2312. 10.2337/diabetes.51.7.2306 [DOI] [PubMed] [Google Scholar]
- Mohseni, F. , Moghbelinejad, S. , & Najafipour, R. (2017). Major components of metabolic parameters and nutritional intakes in different genotypes of adiponectin +276 G>T gene polymorphism in non‐diabetes and non‐alcoholic iranian fatty liver patients. Avicenna Journal of Medical Biotechnology, 9, 155–161. [PMC free article] [PubMed] [Google Scholar]
- Musso, G. , Gambino, R. , De Michieli, F. , Durazzo, M. , Pagano, G. , & Cassader, M. (2008). Adiponectin gene polymorphisms modulate acute adiponectin response to dietary fat: Possible pathogenetic role in NASH. Hepatology, 47, 1167–1177. 10.1002/hep.22142 [DOI] [PubMed] [Google Scholar]
- Nasr, P. , Ignatova, S. , Kechagias, S. , & Ekstedt, M. (2018). Natural history of nonalcoholic fatty liver disease: A prospective follow‐up study with serial biopsies. Hepatology Communications, 2, 199–210. 10.1002/hep4.1134 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Socha, P. , Wierzbicka, A. , Neuhoff‐Murawska, J. , Wlodarek, D. , Podlesny, J. , & Socha, J. (2007). Nonalcoholic fatty liver disease as a feature of the metabolic syndrome. Roczniki Panstwowego Zakladu Higieny, 58, 129–137. [PubMed] [Google Scholar]
- Stefan, N. , Haring, H. U. , & Cusi, K. (2018). Non‐alcoholic fatty liver disease: Causes, diagnosis, cardiometabolic consequences, and treatment strategies. The Lancet Diabetes & Endocrinology. 10.1016/s2213-8587(18)30154-2 [DOI] [PubMed] [Google Scholar]
- Stefan, N. , Kantartzis, K. , & Haring, H. U. (2008). Causes and metabolic consequences of fatty liver. Endocrine Reviews, 29, 939–960. 10.1210/er.2008-0009 [DOI] [PubMed] [Google Scholar]
- Targher, G. , Bertolini, L. , Rodella, S. , Zoppini, G. , Scala, L. , Zenari, L. , & Falezza, G. (2006). Associations between plasma adiponectin concentrations and liver histology in patients with nonalcoholic fatty liver disease. Clinical Endocrinology, 64, 679–683. 10.1111/j.1365-2265.2006.02527.x [DOI] [PubMed] [Google Scholar]
- Tokushige, K. , Hashimoto, E. , Noto, H. , Yatsuji, S. , Taniai, M. , Torii, N. , & Shiratori, K. (2009). Influence of adiponectin gene polymorphisms in Japanese patients with non‐alcoholic fatty liver disease. Journal of Gastroenterology, 44, 976–982. 10.1007/s00535-009-0085-z [DOI] [PubMed] [Google Scholar]
- Townsend, S. A. , & Newsome, P. N. (2016). Non‐alcoholic fatty liver disease in 2016. British Medical Bulletin, 119, 143–156. 10.1093/bmb/ldw031 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vernon, G. , Baranova, A. , & Younossi, Z. M. (2011). Systematic review: The epidemiology and natural history of non‐alcoholic fatty liver disease and non‐alcoholic steatohepatitis in adults. Alimentary Pharmacology & Therapeutics, 34, 274–285. 10.1111/j.1365-2036.2011.04724.x [DOI] [PubMed] [Google Scholar]
- Wang, Z. L. , Xia, B. , Shrestha, U. , Jiang, L. , Ma, C. W. , Chen, Q. , … Hu, Z. G. (2008). Correlation between adiponectin polymorphisms and non‐alcoholic fatty liver disease with or without metabolic syndrome in Chinese population. Journal of Endocrinological Investigation, 31, 1086–1091. 10.1007/bf03345657 [DOI] [PubMed] [Google Scholar]
- Wei, Z. , Li‐Qun, Z. , Xiao‐Ling, H. , Jian, Q. , & Guo‐Yue, Y. (2016). Association of adiponectin gene polymorphisms and additional gene‐gene interaction with nonalcoholic fatty liver disease in the Chinese Han population. Hepatology International, 10, 511–517. 10.1007/s12072-015-9687-0 [DOI] [PubMed] [Google Scholar]
- Wong, V. W. , Wong, G. L. , Tsang, S. W. , Hui, A. Y. , Chan, A. W. , Choi, P. C. , … Chan, H. L. (2008). Genetic polymorphisms of adiponectin and tumor necrosis factor‐alpha and nonalcoholic fatty liver disease in Chinese people. Journal of Gastroenterology and Hepatology, 23, 914–921. 10.1111/j.1440-1746.2008.05344.x [DOI] [PubMed] [Google Scholar]
- Ye, Y. , Yu, J. , Wang, J. , & Lu, G. (2014). Risk factors of non‐alcoholic fatty liver and their relationship with polymorphisms of adiponectin gene promoter region in the han population in guilin city. Guangdong Medical Journal., 35, 2115–2119. [Google Scholar]
- Yki‐Jarvinen, H. (2014). Non‐alcoholic fatty liver disease as a cause and a consequence of metabolic syndrome. The Lancet Diabetes & Endocrinology, 2, 901–910. 10.1016/s2213-8587(14)70032-4 [DOI] [PubMed] [Google Scholar]
- Younossi, Z. M. , Koenig, A. B. , Abdelatif, D. , Fazel, Y. , Henry, L. , & Wymer, M. (2016). Global epidemiology of nonalcoholic fatty liver disease‐meta‐analytic assessment of prevalence, incidence, and outcomes. Hepatology, 64(1), 73–84. 10.1002/hep.28431 [DOI] [PubMed] [Google Scholar]
- Zhang, C. X. , Guo, L. K. , Qin, Y. M. , & Li, G. Y. (2016). Association of polymorphisms of adiponectin gene promoter‐11377C/G, glutathione peroxidase‐1 gene C594T, and cigarette smoking in nonalcoholic fatty liver disease. Journal of the Chinese Medical Association, 79, 195–204. 10.1016/j.jcma.2015.09.003 [DOI] [PubMed] [Google Scholar]
- Zhou, Y. J. , Li, Y. Y. , Nie, Y. Q. , Yang, H. , Zhan, Q. , Huang, J. , … Huang, H. L. (2010). Influence of polygenetic polymorphisms on the susceptibility to non‐alcoholic fatty liver disease of Chinese people. Journal of Gastroenterology and Hepatology, 25, 772–777. 10.1111/j.1440-1746.2009.06144.x [DOI] [PubMed] [Google Scholar]
