Table 2.

Studies on the role of FTO gene variants and its interaction with physical activity

Subjects	Mean age ± SD, years	Main effect	Reference
FTO: rs9939609 variant
Children
349 healthy children participants of the STRIP study and randomly assigned to lifestyle intervention or control groups	15 years	at age 15 years, leisure-time-PA was not associated with the variant	Hakanen et al., 2009 [44]
Adults
234 Danish obese men and 323 Danish controls	obese: 47.5 ± 5.1 control: 49.9 ± 6.0	the positive association between this variant and fatness is not explained by an effect of this variant on REE, GIT, VO2max or LTPA	Berentzen et al., 2008 [45]
5,722 Danish individuals from the population-based Inter99 study sample	TT subjects: 46.2 ± 8 TA subjects: 45.9 ± 8 AA subjects: 46.5 ± 8	association of the A-allele with both overweight and obesity; in homozygous carriers of the A-allele, physical inactivity associates with a relatively large increase in BMI compared with noncarriers and heterozygous for the A-allele	Andreasen et al., 2008 [34]
2,511 Finnish and 15,925 Swedish non-diabetic middle-aged adults	at baseline: 45.5 ± 6.9 follow-up: 68.5 ± 5.6	no evidence of an interaction between the FTO variant and physical activity on BMI	Jonsson et al., 2009 [46]
743 obese individuals from eight clinical centers in seven European countries	37.1 ± 7.9	the association between this variant and obesity may not be mediated by modulation of EE in obese individuals	Goosens et al., 2009 [47]
Other FTO variants Adults
Participants from the EPIC-Norfolk Study.  20,374 participants at baseline and 11,909 participants during follow-up	at baseline: men: 59.1 ± 9.3 women: 58.6 ± 9.3 follow-up: men:63.0 ± 9.0 women: 61.9 ± 9.0	T risk allele of rs1121980 was significantly associated with BMI and WC; PA level attenuated this effect on BMI and WC	Vimaleswaran et al., 2009 [43]
704 healthy Old Order Amish adults, selected from the HAPI study	43.6 ± 3.4	26 FTO SNPs were associated with BMI; the increased risk of obesity due to FTO variants can be blunted through PA; the association is much smaller and no significant in subjects having higher physical activity levels	Rampersaud et al., 2008 [42]

REE = Resting energy expenditure; EE = energy expenditure; GIT = glucose-induced thermogenesis; VO₂max = maximum oxygen uptake;

LTPA = leisure-time physical activity; STRIP = Special Turku Coronary Risk Factor Intervention Project; PA = physical activity;

EPIC = European Prospective Investigation into Cancer and Nutrition-Norfolk Study; HAPI = Heredity and Phenotype Intervention Heart Study.