Seasons Have a Profound Effect on How Human Genes Work

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Seasons – Deep Effect on Working of Human Genes

According to scientists, the seasons tend to have a deep effect on the working of human genes which explains why some of the ailments get aggravated in winter. As per Nature Communications, they found genes involved with immunity where the body’s defence against infections seemed to be more active during the cold months.

Though it could help in combating off viruses like flu it could also activate or worsen conditions like arthritis, where the body attacks itself, according to them. Blood and tissue samples were analysed by the international team of researchers from over 16,000 people living all over the world and out of the 22,000 genes, they scrutinised, that is almost all the genes that humans possess, clear signs of seasonal variation was shown only in a quarter of them.

The changes in the genes which drew the attention of the researchers, the most, were the ones which were involved with the immunity and specially inflammation. These genes tend to get more active during cold winter months between December to February for those living north of the globe and June to August for those in the southern part of the world.

Different Pattern – Immunity/Inflammation Connected to Rainy Season

While studying people residing close to the equator, where the temperatures seems to be fairly high throughout the year, they observed a different pattern where immunity and inflammation seems to be connected to the rainy season, where ailments like malaria tend to be more common.

According to Prof John Todd, one of the study authors based at Cambridge University in the UK observed that the findings could explain why people were prone to certain diseases at a particular time of the year. In Iceland, fewer seasonal changes were found since it is cold most part of the year.

Inflammation tends to have an important role with regards to conditions like rheumatoid arthritis, type-1 diabetes as well as heart disease which is greatest in the winter in countries like the UK. Prof Todd informs that `in the UK, there is a rise in new cases of type-1 diabetes in January, February and March. The results indicate that part of the reason for the same is heightened inflammation and gene activity which is involved’.

Several Factors Responsible in Developing Ailment

He further adds that it was hard to get out exactly what was going on, since several factors tend to influence the person’s chance of developing an ailment. Similarly, other disease and factors like nutrition and stress could also affect how the genes function. Professor of genetic epidemiology at King’s College London, Tim Spector, states that `another dimension that could of importance are the gut microbes which also tend to change between seasons and could be responsible in these changes due to seasonal changes in diet.

Another professor, Prof Tim Hubbard also from King’s stated that there could be an evolutionary advantage behind the seasonal changes the researchers identified. He also adds that` in prehistoric humans, these seasonal changes in inflammation would help to fight infection’. The other seasonal changes they envisaged were in genes linked to metabolism, which according to Todd would help with preserving energy to survive in case of shortage of food and shelter.