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Global Translational Medicine FTO gene and obesity

Figure 4. Map of the linkage disequilibrium of FTO polymorphic variants.

As shown in Figure 3, the genotype frequencies of FTO rs4783819 (r = 0.96), while the rs7206790 variant was not
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rs11075990 polymorphic variants correlate with BMI. The linked to any of the polymorphic variants tested.
A/A genotype occurs less frequently with an increasing Eight polymorphic variants of the FTO gene for which
BMI in the groups under study. People with the A/A a statistically significant association with BMI were
genotype are more often characterized by normal weight shown constitute one block of linkage disequilibrium
compared to heterozygote and minor G/G homozygote (r = 0.82–1.0, P < 0.001) and form two most common
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carriers. haplotypes: A/C/T/T/G/T/G/C (51.9%) and G/T/C/G/
A meta-analysis performed by Peng et al. , which T/A/A/T (42.8%). The frequency of occurrence of other
[12]
includes 59 studies, showed a significant association haplotypes does not exceed 2%.
between a risk for obesity and five polymorphic variants of It is of particular interest that the variants associated
the FTO gene located in the 47-kb linkage disequilibrium with a risk for overweight form one block of linkage
block covering the parts of the first two introns and the disequilibrium (r = 0.82–1.0, P < 0.001). Therefore, to
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exon 2: rs9939609 (OR = 1.31, 95% CI = 1.26–1.36), determine an obesity risk, carrying out genetic testing
rs1421085 (OR = 1.43, 95% CI = 1.33–1.53), rs8050136 for one of these polymorphic variants seems to be
(OR = 1.25, 95% CI = 1.13–1.38), rs17817449 (OR = 1.54, sufficient. This greatly facilitates a process of determining a
95% CI = 1.41–1.68), and rs121980 (OR = 1.34, 95% predisposition to excess weight with the aim to undertake
CI = 1.10–1.62). rs9940128 variant, associated with a preventive measures for identified individuals and reduce
risk for early and severe obesity development, belongs the relevant cost.
to the same block of linkage disequilibrium . However,
[25]
the formation of linkage disequilibrium blocks seems However, several limitations should also be noted.
to have ethnic features. Thus, the strength of the linkage First, neither thyroid disease nor Type 2 diabetes and their
disequilibrium of rs10852521 at rs9939609 varied, pharmacological treatment were exclusion criteria for the
according to the HapMap data, from D’ = 0.48 to D’ = 1.0 present study. Second, we cannot completely exclude the
depending on the population . role of environmental variables, which may impact the
[26]
development of obesity, such as a lifestyle, physical activity,
The analysis results on the linkage disequilibrium of a diet, and alcohol consumption.
FTO polymorphic variants based on genotyping results are
shown in Figure 4 (r values provided). 4. Conclusions
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According to the data, we were able to obtain, the A group of 655 volunteers residing in the territory of the
rs10852521 polymorphic variant turned out to be linked Republic of Belarus was genotyped for 13 polymorphic
to the rs8047395 variant (r = 0.95) and rs1477196 to variants of the FTO gene. A significant association
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Volume 2 Issue 2 (2023) 7 https://doi.org/10.36922/gtm.352