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 Table of Contents  
REVIEW ARTICLE
Year : 2019  |  Volume : 4  |  Issue : 4  |  Page : 104-114

The relationship between fat mass and obesity-associated gene polymorphism and obesity among children in China: A systematic review and meta-analysis


1 Department of Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
2 Institute for Physical Activity and Nutrition, Deakin University, Burwood, Vitoria, Australia
3 Faculty of Medicine, University of Ottawa, Ontario, Canada
4 Department of Accident and Emergency Medicine, Basingstoke and North Hampshire Hospital, Hampshire, UK
5 Department of Pediatric Cardiology, Guangzhou Children's and Women's Medical Center, Jinan University, Guangzhou, China
6 School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, NSW, Australia

Date of Submission02-Dec-2019
Date of Acceptance03-Dec-2019
Date of Web Publication31-Dec-2019

Correspondence Address:
Cunchuan Wang
Department of Bariatric Surgery, The First Affiliated Hospital of Jinan University, Guangzhou 510 630
China
Dr. Sheikh Mohammed Shariful Islam
Institute for Physical Activity and Nutrition, Deakin University, Burwood, Vitoria 3025
Australia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jncd.jncd_43_19

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  Abstract 


The fat mass and obesity-associated (FTO) gene has been shown to be associated with obesity in different populations. However, this association in the Chinese population has been controversial. We evaluated the association of the FTO rs9939609 gene polymorphism with the risk of overweight and obesity in Chinese children and adolescents in a systematic review and meta-analysis. We searched PubMed, Embase, Cochrane Library, and two electronic Chinese databases (CBM, CNKI). Two authors screened abstracts, full-texts, and extracted data according to the prespecified inclusion criteria. A modified STREGA score was used for quality assessment. A random-effects and fixed-effects model was used to conduct the measure the association between FTO gene and obesity. Ten studies including 12,879 participants were included. The FTO rs9939609 gene polymorphism was associated with a statistically significant increased risk of obesity or overweight in Han Chinese children and adolescents (P < 0.05), but absent in the Zhuang and Hazakh Chinese population (P > 0.05). The pooled OR for the codominant genetic model between AA and TT was 1.79 (95% confidence interval: 1.34–2.39, P < 0.0001). Allele A carriers were at greater risk of obesity and overweight compared to noncarriers. Screening for FTO rs9939609 gene polymorphism might help to identify adolescents at risk of developing obesity and consider appropriate prevention strategies.

Keywords: Fat mass and obesity associated gene, meta-analysis, obesity, overweight, rs9939609 gene polymorphism


How to cite this article:
Dong Z, Shariful Islam SM, Yu AM, Razi F, Gupta RK, Moni MA, Wang C. The relationship between fat mass and obesity-associated gene polymorphism and obesity among children in China: A systematic review and meta-analysis. Int J Non-Commun Dis 2019;4:104-14

How to cite this URL:
Dong Z, Shariful Islam SM, Yu AM, Razi F, Gupta RK, Moni MA, Wang C. The relationship between fat mass and obesity-associated gene polymorphism and obesity among children in China: A systematic review and meta-analysis. Int J Non-Commun Dis [serial online] 2019 [cited 2020 Apr 3];4:104-14. Available from: http://www.ijncd.org/text.asp?2019/4/4/104/274463




  Introduction Top


Obesity has reached epidemic proportions globally and its prevalence is increasing at an alarming rate, affecting people of all ages in both the developed and developing countries.[1],[2],[3] China has the largest number of obese people worldwide, with 43.2 million men and 46.4 million women suffering from obesity with an increasing trend over the past decades.[4] The incidence of childhood obesity in China among children 0–7 years has increased nearly seven times (0.8%–5.9%) from 1986 to 2010.[5] Overweight and obese children are at increased risk for a number of diseases, including diabetes, cardiovascular diseases, cancer, mental illnesses, leading to increased morbidity and mortality in adulthood.[6],[7]

Obesity in children and adolescents is caused by a variety of factors including multiple genes, metabolic disorders, and environmental factors including excessive energy intake, poor diet, and lack of exercise.[8],[9] In families where both parents are obese, children have 70%–80% greater risk of obesity. Conversely, in families where parents are not obese, the risk of childhood obesity is only 7%.[10] The occurrence of obesity in children and adolescents might result from genetic predisposition or the same lifestyle from their parents.

A landmark study by Frayling et al.[11] showed that the fat mass and obesity-associated (FTO) gene predisposes to diabetes through an effect on body mass index (BMI) with 1.7 times higher odds of obesity. The FTO gene is expressed in the cell nucleus of majority human tissue with the highest levels in the brain, where it is believed to contribute toward energy homeostasis and eating behavior. The FTO gene was the first reliable candidate gene related to obesity in the general population, discovered by the genome-wide association study. The human FTO gene is located on 16ql2.2, with a length of 400 kb, including 9 exons, all encoding the protein.[12] It has a 61 kb area of 5 'upstream region of 47 kb gene intron (KIAA1005 gene), and is downstream of gene adjacent to the Iroquois gene family.[13] Further, Tanofsky-Kraff et al.[14] found that children and young people who carry the FTO gene variant rs9939609 are more inclined to intake high-fat food, eat “out of control,” and become obese. Currently, the FTO gene associated with the type 2 diabetes single-nucleotide polymorphism (SNP) site remains the best candidate for genetic obesity research.[13]

A few studies examined the genetics of obesity as it relates to specific ethnicity. Liu et al.[15] observed an association between rs9939609 and obesity-related risk factors between races. Two meta-analyses by Quan et al.[16] and Liu et al.[17] showed that the FTO rs9939609 polymorphism is a risk factor for obesity in children and adolescents. However, this study did not specify whether there are differences in patients of varying ethnicity and included only one study from China. However, despite considerable efforts, there are no examples of common genetic variants that explain the association of the FTO gene with childhood obesity in the Chinese population. Further research examining the relationship between the obesity of children and genetics is of great significance to attempt to identify at-risk populations and provide early interventions to prevent childhood obesity. This systematic review and meta-analyses were performed to investigate the relationship between the FTO rs9909609 gene with obesity or overweight and BMI. The primary objective of this study is to provide a more reliable estimate of the significance of this genetic association in the Chinese children and adolescent population and to describe the influence of ethnicity subgroups on this correlation.


  Methods Top


Search strategy

A systematic literature search was performed by two authors using electronic databases of PubMed, Embase, Cochrane Library, China Biological Medicine Database-CBM, and Chinese National Knowledge Infrastructure Database-CNKI, from 1950 to September 22, 2016. The following key search terms were used: “FTO gene rs9939609” OR “rs9939609” AND “fat mass and obesity-associated gene” OR “FTO” and “obesity” OR “overweight” and “children” OR “adolescents” AND “Chinese” OR “China.” References lists of selected studies and reviews were also screened to identify potentially relevant studies.

Inclusion criteria and exclusion criteria

Titles, abstracts, and full-text screening were performed independently and in duplicate by two reviewers (ZD and WL) using the prespecified inclusion and exclusion criteria. Included studies were limited to those published in Chinese or English. Inclusion criteria required studies investigating the association of FTO (rs9939609) gene polymorphism and obesity or overweight in children or adolescents. Children or adolescents were defined as those <18 years old. Studies designed as case–controlled, cohort, or cross-sectional studies comparing obese or overweight individuals to nonobese healthy control groups, investigating gene distribution groups in line with the Hardy–Weinberg equilibrium (HWE) and those with participants evaluated using the BMI criteria for obesity and overweight status were included in the study.[17] Included outcomes were independent data presented as odds ratio (OR) or relative risk with 95% confidence intervals (CI) or data to calculate the OR and P values.

Excluded studies were nonhuman studies, those that did not investigate the FTO rs9939609 gene polymorphism, deviated from the HWE or did not assess obesity or overweight using BMI. Studies designed as reviews, case reports, or those that reported incomplete data or adults were excluded from the study.

Data extraction

Two reviewers (DZ, WL) independently extracted the following prespecified outcomes from each included study: first author, year of publication, ethnicity, district, study design, genotype, testing method, gender, age, sample size, the number of case group and the control group for rs9939609) genotype, and the result of HWE test. For studies that included both children and adult participants, data were extracted for only children and adolescents.

Quality assessment

The two reviewers (DZ, WL) independently assessed the quality of the included studies, using a modified Strengthening the Reporting of Genetic Association Studies (STREGA) score quality assessment tool.[18],[19] The STREGA scores were based on the traditional epidemiologic considerations and genetic issues and ranged from 0 (low quality) to 22 (high quality). Disagreements between the reviewers were resolved by discussion.

Statistical analysis

Data analyses were performed using the RevMan 5.3 Review Manager (RevMan) version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014) meta-analysis software. The association of the rs9939609 polymorphism with the risk of obesity or overweight was estimated by calculating a pooled OR with 95% CI for BMI. The pooled ORs with 95% CIs were reported using the codominant model (AA vs. TT or AT vs. TT), dominant model (AA + AT vs. TT), recessive model (AA vs. AT + TT), and allelic model (A vs. T). Subgroup analyses under the allelic model were grouped by participants (children, children, and adolescents) and ethnicity (Caucasian, Han, Uygur, others). The heterogeneity of included studies was assessed with the Cochran's Q (P) statistic and the I2 test. If statistical heterogeneity was present with I2 ≥ 50%, a random effects model was performed; otherwise, if there was little or no heterogeneity, a fixed effects model was used. In the present study, the fixed effects model was selected for homogeneous outcomes (P ≥ 0.05 and I2 < 50%) and the random effects model was applied for heterogeneous outcomes (P < 0.05 or I2 ≥ 50%). A sensitivity analysis was also performed. An alpha level of 0.05 was considered statistically significant. Publication bias was assessed using the Begg's and Egger's approaches using Stata 13.0 (StataCorp LP, College Station, TX, USA), and a funnel plot was constructed, whereby asymmetry was assessed using Egger's regression test.[20],[21],[22],[23]


  Results Top


Literature search

A total of 1650 studies were identified: 223 from Chinese Databases (CNKI, n = 133; CBM, n = 90) and 1427 from non-Chinese databases including PubMed (n = 623), EMBASE (n = 803), and Cochrane CENTRAL (n = 1). Title and abstract screening yielded 376 potentially relevant studies, which were assessed for eligibility through full-text screening. A total of 366 studies were excluded in full-text screening as they did not meet study inclusion criteria (adult studies, case reports, randomized controlled trials, meta-analysis, and reviews). Finally, 10 studies were selected for the meta-analysis, including a total of 12,879 participants (6045 cases with obesity or overweight and 6834 controls). All the included studies were published from 2010 to 2015 and were in line with the HWE.[24],[25],[26],[27],[28],[29],[30],[31],[32],[33]

Study characteristics

[Figure 1] demonstrates the study flow diagram of our meta-analysis. The characteristics of the included studies are presented in [Table 1] and [Table 2]. All included studies were case-control studies, that varied in sample size (n = 279 to n = 3924), and enrolled children, adolescents, or both. Of the included studies, most were performed on the Han population, with the exception of two studies where participants were of Zhuang and Hazakh ethnicity.
Figure 1: Flow diagram of the search process and study selection

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Table 1: Genetic characteristics of included studies

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Table 2: General characteristics of included studies

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Codominant model

All ten included studies reported raw data on AA, AT, TT. In the AA versus TT group, there was moderate heterogeneity observed by the fixed effects model (χ2 = 27.52, P < 0.001; I2 = 67%). Results of a sensitivity analysis found that heterogeneity was eliminated with the exclusion of one study.[29] The results of a meta-analysis of nine remaining studies showed that the FTO gene rs9939609 polymorphism was significantly associated with an increased risk of obesity or overweight. The pooled ORs for the codominant genetic model between AA and TT was 1.79 (95% CI: 1.34–2.39, P < 0.0001). Subgroup analyses were performed based on Han, Zhuang, or Hazakh ethnicity. No heterogeneity was found in the subgroup analyses with the Yang et al. 2014[29] study excluded. In the subgroup of Han ethnicity studies, a statistically significant difference was observed when comparing AA with TT (OR = 1.87, 95% CI: 1.38–2.53, P < 0.0001). This difference was neither observed in other subgroups of Zhuang ethnicity (OR = 1.24, 95% CI: 0.32–4.74, P = 0.75) nor Hazakh ethnicity (OR = 0.95, 95% CI: 0.21–1.43, P = 0.95). The results are presented in [Figure 2].
Figure 2: Meta-analysis of AA versus TT of the codominant model. A statistically significant difference was observed when comparing AA with TT (odds ratio = 1.87, 95% confidence interval: 1.38–2.53, P < 0.0001) in Han ethnicity studies. This difference was neither observed in other subgroups of Zhuang ethnicity (odds ratio = 1.24, 95% confidence interval: 0.32–4.74,P= 0.75) nor Hazakh ethnicity (odds ratio = 0.95, 95% confidence interval: 0.21–1.43,P= 0.95)

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In the AT versus TT group, initial heterogeneity was observed among the ten included studies by the fixed effects model (χ2 = 76.48, P < 0.00001; I2 = 88%). Following a sensitivity analysis, the random-effects model was used to perform the meta-analysis. The results of the meta-analysis showed that the FTO gene rs9939609 polymorphism was significantly associated with an increased risk of obesity or overweight when comparing AT versus TT. The pooled ORs for the codominant genetic model comparing AT with TT was OR = 1.55 (95% CI: 0.96–2.52, P = 0.0002). Subgroup analyses were performed on Han, Zhuang, and Hazakh ethnicities. Due to heterogeneity, the random-effects model was used. In the subgroup of Han ethnicity studies, there was a statistically significant difference comparing AT with TT: (OR = 1.78, 95% CI: 1.27–2.50, P = 0.0008). No statistical difference was observed when comparing AT with TT in the Zhuang ethnicity subgroup (OR = 1.64, 95% CI: 0.91–2.93, P = 0.10), or Hazakh ethnicity subgroup (OR = 1.55, 95% CI: 0.96–2.52, P = 0.08). The results are presented in [Figure 3].
Figure 3: Meta-analysis of AT versus TT of the codominant model. There was a statistically significant difference comparing AT with TT: odds ratio = 1.78 (95% confidence interval: 1.27–2.50,P= 0.0008) in Han ethnicity studies. No statistical difference was observed when comparing AT with TT in the Zhuang ethnicity subgroup (odds ratio = 1.64, 95% confidence interval: 0.91–2.93,P= 0.10), or Hazakh ethnicity subgroup (odds ratio = 1.55, 95% confidence interval: 0.96–2.52,P= 0.08)

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Dominant model

In AA + AT versus TT group, potential heterogeneity was detected by the fixed effects model (χ2 = 87.28, P < 0.00001; I2 = 90%). Following a sensitivity analysis, a random-effects model was used to perform the meta-analysis. The pooled ORs for the codominant genetic model between AA + AT and TT was (OR = 1.79, 95% CI: 1.64–1.96, P < 0.00001). Subgroup analyses were performed on Han, Zhuang, and Hazakh ethnicities. In the subgroup of Han ethnicity, there was a statistically significant difference when comparing AA + AT with TT (OR = 1.81, 95% CI: 1.66–1.98, P < 0.00001). However, this difference was neither observed in the Zhuang ethnicity subgroup (OR = 1.58, 95% CI: 0.91–2.74, P = 0.10) nor the Hazakh ethnicity subgroup (OR = 0.51, 95% CI: 0.94–2.44, P = 0.09). The results are presented in [Figure 4].
Figure 4: Meta-analysis of AA + AT versus TT of the dominant model. There was a statistically significant difference when comparing AA + AT with TT (odds ratio = 1.81, 95% confidence interval: 1.66–1.98, P < 0.00001) in the subgroup of Han ethnicity. However, his difference was neither observed in the Zhuang ethnicity subgroup (odds ratio = 1.58, 95% confidence interval: 0.91–2.74,P= 0.10) nor the Hazakh ethnicity subgroup (odds ratio = 0.51, 95% confidence interval: 0.94–2.44, P = 0.09)

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Recessive model

In AA versus AT + TT group, potential heterogeneity was detected by the fixed effects model (χ2 = 20.29, P = 0.02; I2 = 56%). Following a sensitivity analysis and exclusion of the Yang et al. 2014[29] study, the fixed-effects model showed that the pooled ORs for the codominant genetic model between AA and AT + TT was OR = 1.56 (95% CI: 1.17–2.03, P = 0.81). Subgroup analyses on Han, Zhuang, and Hazakh ethnicities reported a statistically significant difference comparing AA with AT + TT in the Han ethnicity (OR = 1.63, 95% CI: 1.21–2.19, P = 0.001). This difference was neither observed in the Zhuang ethnicity subgroup (OR = 1.11, 95% CI: 0.29–4.23, P = 0.88) nor the Hazakh ethnicity subgroup (OR = 0.77, 95% CI: 0.17–1.43, P = 0.73). The results are presented in [Figure 5].
Figure 5: Meta-analysis of AA versus AT + TT of the recessive model. In the subgroup of studies, a statistically significant difference was observed comparing AA with AT + TT in the Han ethnicity (odds ratio = 1.63, 95% confidence interval: 1.21–2.19,P= 0.001). This difference was neither observed in the Zhuang ethnicity subgroup (odds ratio = 1.11, 95% confidence interval: 0.29–4.23,P= 0.88) nor the Hazakh ethnicity subgroup (odds ratio = 0.77, 95% confidence interval: 0.17–1.43,P= 0.73)

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Allelic model

Seven included studies reported the raw data of A and T. In the A versus T group, there was potential heterogeneity in the fixed effects model (χ2 = 43.74, P < 0.00001; I2 = 86%). Following a sensitivity analysis, the random-effects model showed that the pooled ORs for the codominant genetic model between A and T was (OR = 2.62, 95% CI: 1.57–4.40, P = 0.0002). Subgroup analyses were performed on Han, Zhuang, and Hazakh ethnicities. In the subgroup of studies, there was a statistically significant difference observed when comparing AA with AT + TT in the Han ethnicity subgroup (OR = 3.54, 95% CI: 1.71–7.33, P = 0.0007). However, this difference was not observed in the Zhuang ethnicity subgroup (OR = 1.44, 95% CI: 0.89–2.35, P = 0.14) or the Hazakh ethnicity subgroup (OR = 1.52, 95% CI: 0.90–2.57, P = 0.11). The results are presented.

Quality assessment of the included studies

The modified STREGA score was performed to assess the methodological quality of included studies.[19] A summary of quality assessment scores is presented in [Table 3]. All included studies were of adequate methodological quality for comparison.
Table 3: Modified Strengthening the Reporting of Genetic Association Study quality assessment of included studies

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Publication bias

Publication bias was evaluated using the Begg's test and Egger's test. In the analysis for the association of FTO gene rs9939609 polymorphism with obesity or overweight in Han, Zhuang and Hazakh ethnicity, no significant publication bias was shown for overall ethnicity by using the Begg's test and Egger's test (P r > lzl = 0.095). A forest plot is presented in [Figure 6].
Figure 6: No significant publication bias was shown by using the Begg's test and Egger's test (P r > lzl = 0.095)

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  Discussion Top


The results of the meta-analysis showed that FTO gene rs9939609 polymorphism was associated with a statistically significant increased risk of obesity or overweight among the Han Chinese children and adolescents. This relationship was absent in the Zhuang and the Hazakh Chinese population. Allele A carriers of the FTO risk gene rs9939609 are at significantly higher risk than noncarriers in the codominant genetic model, dominant model, recessive model, and allelic model. These results are consistent with previous reports.

FTO gene polymorphism has been shown as a genetic risk factor for the development of obesity and overweight in several studies. A study by Quan et al.[16] found that the FTO rs9939609 polymorphism was significantly associated with the risk of obesity among children and adolescents, and the allele A of rs9939609 might increase the risk. Peng et al.[34] investigated 41,734 obesity cases and 69,837 healthy controls and showed that there were significant associations between obesity risk and rs9939609 (OR = 1.31, 95% CI: 1.26–1.36). A study by Elks et al.[35] showed that the locus of allele A of the FTO gene rs9939609 were positively correlated with birth weight at 6 weeks, and has the potential to protect against neonatal weight gain and malnutrition. Further, Wardle et al.[36] considered the T allele to have the potential to enhance internal satiety signals, and suppressing overeating.

It is well known that the FTO gene polymorphism rs9939609 has various genotypes: AA, AT, and TT.[37],[38],[39],[40],[41] Quan et al.[16] showed that FTO rs9939609 polymorphism was significantly associated with the increased risk of obesity in the codominant model, dominant model, recessive model, and the allelic model among Caucasian children and adolescents. Liu et al.[17] reported that variant in FTO gene was significantly associated with increased risk of overweight/obesity in Caucasians, Asians, and American Indians children and adolescents (OR = 1.35; 95% CI: 1.27–1.44, P < 0.001). The overall pooled ORs for the risk of obesity and overweight was 1.34 and 1.35, respectively, excluding the African children and adolescents. Kochetova et al.[42] also reported that the FTO rs9939609 gene is associated with obesity risk following an additive model. These studies all support our findings. Rutters et al.[43] found that the FTO A allele (rs9939609) is associated with higher BMI, fat mass index, and leptin concentrations from Dutch children and adolescents. Hotta et al.[44] considered that SNPs in FTO were associated with severe obesity in the Japanese. A study by Kochetova et al.[42] showed an association of quantitative parameters (age, weight, and BMI) with two the FTO rs9939609 and rs9930506 SNPs and the association of age and the MC4R rs12970134 SNP. The study demonstrated the role of genetic variability in FTO and MC4R genes in obesity development in Tatar women from Russia. Horikoshi et al.[45] found that rs8050136 in FTO showed a nominal significance in terms of the association with T2D in the Japanese population.

Although numerous studies support the relationship between the FTO gene rs9939609 and human obesity, the mechanism by which the FTO rs9939609 gene directly causes obesity is unclear.[17],[43],[44],[45] It is hypothesized that the FTO gene is highly expressed in the hypothalamus' arcuate nucleus, hypothalamic paraventricular nucleus, dorsomedial nucleus, and ventromedial nucleus, whereby food intake and energy metabolism is regulated in the bran, or that FTO is likely to be an integral part of a neural regulatory pathway involved in energy metabolism in adipose tissue.[46],[47] FTO rs9939609 gene mutation may lead to increased or disordered gene expression of FTO, and that carriers of the risk allele may not exhibit changed energy consumption.[48] Zhang et al.[49] and Cecil et al.[50] demonstrated that the FTO rs9939609 gene mutation may be correlated with gender, age, obesity, food intake, energy expenditure, and lifestyle in children and adolescents.

Obesity is a risk factors for diabetes, cardiovascular disease (CVD), cancer and other chronic diseases. Liu et al.[40] analyzed rs9939609 and rs8050136 variants in 4189 Chinese Han population, and indicated that the two variants in the FTO gene contribute to obesity and type 2 diabetes in the Asian populations. Huang et al.[51] reported that the rs9939609 polymorphism may be involved in the susceptibility of endometrial cancer and pancreatic cancer, especially in Asian populations. Loos et al.[52] found the rs17782313 polymorphism near the MC4R gene associated with obesity among both European adults (OR = 1.12, 95% CI: 1.08–1.16, P < 0.05) and children (OR = 1.30, 95% CI: 1.20–1.41, P<0.05). Thorleifsson et al.[53] also suggested that rs12970134 near the MC4R gene increase the risk of obesity among Europeans. Xi et al.[54] confirms the significant association of MC4R polymorphism with the risk of obesity. Other genes rs8050136, rs1121980, rs1421085, and rs1558902 also have been shown as a risk factor for obesity.[40],[42] Thus, rs9939609 and its related genes may be a potential biomarker in the early diagnosis or gene therapy target of endometrial cancer and pancreatic cancer. Further research on the role of the FTO gene is necessary for the prevention of CVD, diabetes, cancer or chronic diseases through prompt screening, early-targeted inventions to prevent, diagnose, optimum management of obesity.[51],[52]

A limitation of the present meta-analysis is the presence of heterogeneity among trials; however sensitivity analysis and random-effects models were used in an attempt to account for this variance. Further, potential publication bias may have been present, as unpublished studies would not have been captured by the literature search. This study was also limited as it included studies only on the Han, Zhuang, and Hazakh ethnicity, while the remaining subsets of the Chinese population were not analyzed. Future works should entail a sub-analysis of children and adolescents by age, gender, socio-economic status, and lifestyle habits such as exercise and nutrition. Public health programs should adopt genetic risk score-based genetic and racial predisposition, to develop individualized prevention and treatment programs for children and adolescents at risk of developing obesity or overweight. Ultimately, such evidence will enhance overweight and obesity prevention and support the treatment of childhood obesity, by targeting preventative therapies, thereby reducing the risk of future diabetes, CVD, and other obesity-related diseases.[55]


  Conclusions Top


Our study confirms that the rs9939609 gene polymorphism is associated with a statistically significant increased risk of overweight and obesity in Han Chinese children and adolescents. Further, allele A carriers are at higher risk of developing obesity and overweight compared to noncarriers of allele A. Future research is warranted to investigate lifestyle and other contributory factors to the pathogenesis of increased fat mass and obesity as it relates to the rs9939609 gene polymorphism.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Figures

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    Tables

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