What specific types of genes are highly susceptible to suffer from obesity?

In westernized countries especially, the accessibility of ample, energy-rich processed foods in the last few decades has resulted in a sharp rise in the occurrence of obesity. Obesity is a key risk aspect for the various disease like pulmonary diseases, cardiovascular diseases, psychiatric illness metabolic related diseases (e.g. diabetes), osteoarticular diseases, some cancer also etc.

In the 1960s, Neel gave the 'thrifty gene' hypothesis, explaining there are some genes which enable individuals to competently collect and process food to store fat when there is an abundance of food. So, during starvation time stored fat can be decomposed to provide energy to the body. People who possess these genes generally not becoming only slightly overweight, but exceptionally obese. According to USA studies, such kind of people can be seen in high-risk groups, like African-Americans, Pima Indians, Hispanic-Americans and Pacific Islanders. Scientific studies demonstrate that genetics plays a significant role in obesity. Genes can be able to cause obesity directly in some of the syndromes like Bardet-Biedl syndrome, Prader-Willi syndrome etc. Obesity is a highly complex disease with consequence of the interactions of an extensive variety of genetic and environmental factors.

It is now investigated that overweight persons and their forms are related within a family. Obesity risk increased from two to eight folds for a person with a personal family history as compared to those with no family history related to obesity. As the transfer of heredity, obesity gene may link to body fat from 5 to 40%, adipose tissue density, and occurrence rate from 40 to 55%. The increase in body weight and adipose gain upsurge with an increase in age, also affected by heredity that is ultimately linked to the gene. Incidences of monogenic types of obesity are instigated by genetic mutations. The utmost common forms of obesity are undoubtedly the outcome of variations within a large and different amount of genes. Sequence variants inside a pool of 56 different genes were reported as being linked to obesity phenotypes, however, only a few showing positive results in different studies.

Few genes associated with obesity due to monogenic effects and Mendelian disorder reported in previous years summarized below:

There is presently 22 gene linked to five positive and confident studies (mentioned below). These genes comprise members of the various metabolic pathway like leptin-melanocortin pathway, pro-inflammatory cytokines, and various uncoupling proteins.

Some genes related to obesity are as follows:                                                           

Beside these, it's also needed to understand that environment factors also playing a significant role in causing obesity. Environmental factors directly influence the activation and deactivation of the mentioned gene. Significantly identification of those genes will surely help in elucidating the etiology related to obesity and its metabolic significances. With this knowledge further it will ease the identification of their risk factor in relations of their genetic profile to develop their personalized treatment approaches.

Conclusion:

It is concluded that genes do not permanently predict future fitness. Genes and environmental factors both be required for a person to become overweight. In some cases multiple genes may upsurge one's vulnerability for obesity with required outside factors; such as lavish food supply with less physical movement. Scientists have found numerous obesity susceptibility genes and the mixture of an obesogenic atmosphere will obviously causing obesity development in any individual. Though, sometimes it is likely possible to be obese without having any role of any candidate gene.