Characterization of Fat Mass Obesity Gene and Its Variants


Characterization of Fat Mass Obesity Gene and Its Variants

The occurrence of obesity is still increasing despite controlling the lifestyle changes associated with eating habits and exercise. The risk of obesity depends on entangled factors; i.e., genetic variants or polymorphism and environmental factors which includes diet and physical activities1.

Genes can interact with other genes or with external factors (diet) to contribute to increased body fat. Previous studies found that genes play a role in nutrient-specific choices and eating preferences. Genetic variations may explain individual-specificities in food preferences, nutritional requirements and dietary responses among individuals2.

Fat mass and obesity-associated protein (FTO) is unambiguously found in the nucleus of cells in nearly all human tissues. The hypothalamus is the area where its highest expression levels are observed. This appetite-control zone plays an important role in sensitivity to satiety, food responsiveness and eating behaviour3.

In previous studies it has demonstrated that dietary patterns and composition can be affected by risk variants that are related to obesity. The preference for protein and sucrose is related to risk alleles of the FTO gene and is also related to a high-fat and low-fiber diet and the consumption of carbohydrates and protein4.

In this context a new study was conducted to investigate the relationship between the Fat mass and obesity-associated protein rs9939609 (Single nucleotide polymorphism gene) polymorphism and diet patterns and food preferences in an obese Indonesian population5.

There were no significant differences found in the average total energy, carbohydrates, fat, protein and fiber intakes among the normal and obese groups. However, the obese group was likely to have higher calories, starch and fat than the normal group. The study also found that there was no significant difference in macronutrient intake among FTO variants. Subjects with the A allele were likely to eat less macronutrients than those with the TT genotype.

When adjusted for age, rs9939609 showed a significant correlation with weight, body mass index, hip circumference, % body fat and systolic blood pressure but not with waist circumference and diastolic blood pressure.

Persons with the A allele were shown to eat considerably more fried food than those with the TT genotype. Moreover, a significant relationship between the A allele and lower fruit intake was also found. Furthermore, obese subjects with the A allele do not prefer a diet including fruits-vegetables and meat curry. High fried food intake and low fruit, vegetable and curry intake may increase obesity prevalence in subjects with the A allele.

The potency of the research was that the study had been conducted in numerous samples and various geographic distributions comprising rural and urban subjects. The limitation of the study was that it was a cross-sectional study, which cannot trace causal mechanisms. Based on this limitation, future research will include an intervention study.

Pakistan Journal of Biological Sciences


  1. Cecil, J., M. Dalton, G. Finlayson, J. Blundell, M. Hetherington and C. Palmer, 2012. Obesity and eating behaviour in children and adolescents: Contribution of common gene polymorphisms. Rev. Psychiatry, 24: 200-210.
  2. Bauer, F., C.C. Elbers, R.A.H. Adan, R.J.F. Loos and N.C. Onland-Moret et al., 2009. Obesity genes identified in genome-wide association studies are associated with adiposity measures and potentially with nutrient-specific food preference. J. Clin. Nutr., 90: 951-959.
  3. Dina, C., D. Meyre, S. Gallina, E. Durand and A. Korner et al., 2007. Variation in FTO contributes to childhood obesity and severe adult obesity. Genet., 39: 724-726.
  4. McCaffery, J.M., G.D. Papandonatos, I. Peter, G.S. Huggins and H.A. Raynor et al., 2012. Obesity susceptibility loci and dietary intake in the Look AHEAD Trial. J. Clin. Nutr., 95: 1477-1486.
  5. Susmiati, Lipoeto, N.I., Surono, I.S. and Jamsari, J., 2018. Association of Fat Mass and Obesity-associated rs9939609 Polymorphisms and Eating Behaviour and Food Preferences in Adolescent Minangkabau Girls. J. Nutr., 17: 471-479.