The Fat Mass and Obesity gene (FTO) is associated with the synthesis of the FTO enzyme, also known as the alpha ketoglutarate dependent dioxygenase. FTO gene expression has been shown to be upregulated in the hypothalamus of the brain after food deprivation, which is associated with increased consumption of high calorie foods. There are 3 SNPs that we analyze in association with weight management and carbohydrates, fiber, protein or saturated fat intake- rs9939609, rs8050136 and rs11076023.
Association with a tendency to overeat (Weight Management):
In a review study, children with the A variant of the gene were shown to be associated with greater intake of biscuits when compared with children with the T variant (rs9939609). Adults with the A variant (rs9939609) were also shown to have altered post prandial satiety (feeling of being full) levels. In a similar study conducted to identify the association between post prandial satiety and rs9939609, people with the A variant of the fat gene were found to be associated with low sensation of feeling full after a meal.
Loss Of Control Over Eating
In a study conducted on 289 youth, people with the A variant (rs9939609) of the gene had a greater tendency to eat more fat than people with the T variant (rs9939609), with 37.4% of people with the A variant reporting loss of control over eating when compared with 18.8% of people with the T variant. Subsequently, the study showed that people with the A variant of the gene had a significantly greater body mass index.
TV advertisement and overeating
TV advertisements could also induce people to overeat, but the extent of overeating is shown to be associated with the fat gene variant carried by the individual. A study was conducted on 200 children post lunch, involving screening of a 34 minute television program, which also included food advertisements and toy advertisements. Children with the A variant (rs9939609) of the gene consumed significantly more snacks when they were exposed to food advertisements.
Association with Carbohydrate Intake and Weight Gain Tendency:
In a study conducted on 1618 people from an Asian Indian population, people with the A variant (rs8050136) of the gene had a 2.46% higher risk of obesity when compared to people with the C variant among people on a high carbohydrate diet. In the same study, it was found that among people who were inactive, people with the A variant were found to be associated with 1.89 times increased risk for obesity.
Association with Fibre Intake and Weight Loss Tendency:
In the study on 1618 people from an Asian population, people with the A variant (rs11076023) of the gene were shown to be associated with 1.62cm lower waist circumference than people with the T variant of the gene.
Association with Saturated Fat Intake and Weight Gain Tendency:
In a study conducted to identify the association between fat intake, FTO genotype (rs9939609) and body fat percentage, people with the T variant did not show an increase in body fat percentage with increase in fat intake, but people with the A variant were shown to be associated with increased body fat percentage with increased fat intake.
In a study conducted on 4839 men and women on a high fat diet, people with the A variant (rs9939609) were shown to be associated with higher BMI and were twice as likely to be obese when compared with people with the T variant.
Association with Protein Intake and Weight Loss Tendency:
In a study conducted on 737 overweight adults, people with the A variant of the gene (rs9939609) were shown to be associated with a reduced food craving on a hypo-caloric and a high protein diet.
Association with Type 2 Diabetes:
In a study conducted on 2577 Korean study participants, it was found that people with the A variant (rs9939609) of the fat gene were associated with increased risk for obesity and, thereby, an increased risk for diabetes. In a similar study conducted on 4,189 Han Chinese individuals, people with the A variant of rs9939609 and A variant of rs8050136 were shown to be associated with type 2 diabetes and obesity in the Asian population.
Does your 23andme, Ancestry DNA, FTDNA raw data have FTO gene variant information?
| CHIP Version | FTO SNPs |
| 23andMe (Use your 23andme raw data to know your FTO Variant) | |
| v1 23andme | Present |
| v2 23andme | Present |
| v3 23andme | Present |
| v4 23andme | Present |
| V5 23andme (current chip) | Present |
| AncestryDNA (Use your ancestry DNA raw data to know your FTO Variant) | |
| v1 ancestry DNA | Present |
| V2 ancestry DNA (current chip) | Present |
| Family Tree DNA (Use your FTDNA raw data to know your FTO Variant) | |
| OmniExpress microarray chip | Present |
| Genotype (rs9939609) | Phenotype | Recommendations |
| AA | [Limitation] More likely to have higher risk for obesity. [Limitation] More likely to have higher fat percentage on a high fat diet [Limitation] More likely to have higher BMI on a high fat diet [Limitation] More Likely to have loss of control eating episodes [Limitation] More Likely to have higher risk for type 2 diabetes [Advantage] More likely to have lower food craving on a high protein diet | A common fat gene myth is that people with this variant are doomed to remain overweight or obese, however, practicing mindful eating and consciously avoiding increased consumption of high fatty food could help in better weight management For people with this variant of the fat gene weight loss can be achieved by balancing food intake with appropriate exercises A high protein diet may be beneficial as it reduces food craving. So foods that turn off fat genes are foods that are rich in protein. Spirulina is a rich source of protein and helps improve satiety |
| AT | Moderate risk for obesity | |
| TT | [Advantage] More likely to have lower risk for obesity. [Advantage] Less likely to have higher fat percentage on a high fat diet [Advantage] Less likely to have increased BMI on a high fat diet [Advantage] Less Likely to have loss of control eating episodes [Advantage] Less Likely to have higher risk for type 2 diabetes [Limitation] Less likely to have lower food craving on a high protein diet | Ensure a healthy balance between food intake and exercises |
| Genotype (rs8050136) | Phenotype | Recommendation |
| AA | [Limitation] More likely to have increased risk for obesity. [Limitation] More Likely to have higher risk for type 2 diabetes | Ensure a healthy balance between food intake and exercises |
| AC | Moderate risk for obesity | Though the risk for obesity is lower, practise healthy eating practices and ensure sufficient physical activity |
| CC | [Advantage] More likely to have lower risk for obesity. [Advantage] Less Likely to have higher risk for type 2 diabetes | Though the risk for obesity is lower, practise healthy eating practices and ensure sufficient physical activity |
| Genotype (rs11076023) | Phenotype | Recommendation |
| AA | [Advantage] More likely to have lower waist circumference on a high fiber diet | Consume a fibre rich diet to ensure better weight maintenance Fibre rich foods include black beans, lima beans, broccoli, artichoke and brussels sprouts |
| AT | Moderate waist circumference on a high fiber diet | A fiber rich diet may not considerably lower weight but it helps in bowel movements and in controlling blood sugar levels |
| TT | [Limitation] More likely to have higher waist circumference than people with the A variant on a high fiber diet | A fiber rich diet may not considerably lower weight but it helps in bowel movements and in controlling blood sugar levels |
References:
- https://en.wikipedia.org/wiki/FTO_gene
- https://www.ncbi.nlm.nih.gov/pubmed/19828706?dopt=Abstract
- https://www.ncbi.nlm.nih.gov/pubmed/27249024
- https://www.ncbi.nlm.nih.gov/pubmed/27274759?dopt=Abstract
- http://ajcn.nutrition.org/content/early/2009/09/02/ajcn.2009.27958.abstract
- https://www.ncbi.nlm.nih.gov/pubmed/26440677
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2777464/
- https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/s12986-016-0098-6
- https://www.ncbi.nlm.nih.gov/pubmed/24622803
Related Links:
- https://www.xcode.life/dna-and-health/obesity-and-genetics-variations-in-fto-apoa2-and-apoa5-genes
- https://www.xcode.life/dna-and-nutrition/how-much-of-body-weight-is-determined-by-genetics
“Nutrigenetics, fitness genetics, health genetics are all nascent but rapidly growing areas within human genetics. The information provided herein is based on preliminary scientific studies and it is to be read and understood in that context.”
