Previous studies have all linked obesity to the FTO gene. This particular gene has been associated with increased obesity, increased likelihood of developing depression and malignant melanoma.
Obese people, in whom FTO is over expressed, also have higher levels of a hunger inducing hormone known as ghrelin. However, the researchers from the Massachusetts General Hospital (MGH) found that previous researchers were lacking when they focused on a particular group of people and the genes. All these studies were short-sighted when it came to the effects of the environment on people over a long period of time since these studies targetted people born in a particular year.
“We know that environment plays a huge role in the expression of genes, and the fact that our effect can be seen even among siblings born during different years implies that global environmental factors such as trends in food products and workplace activity, not just those found within families, may impact genetic traits,” explained the researchers.
So the researchers analyzed the data collected for the Framingham Offspring Study where the people born in the years 1971 till 2008 were participants, and had been assessed for their BMI at least 8 times during that duration. Looking at these assessments, the researchers were able to observe the trends between obesity and FTO expression. The researchers noted that there was a net increase in the gene over expression after the world war and was significantly absent before the year 1942. These were the years when technology was on the rise and processed foods gained popularity.
Regarding the results the researchers said, “These results – to our knowledge the first of their kind – suggest that this and perhaps other correlations between gene variants and physical traits may vary significantly depending on when individuals were born, even for those born into the same families.”
This study is an excellent example of just how much changes in our environment can produce a change in our genetic makeup, and the gene expression we see now may not always have been present but may be seen due to the changes in our environment. Similarly, the study may also provide an insight about how future risk factors may develop because of the environment we see now.