Have Scientists Pinpointed The Gene Responsible For Weight Gain and Aging?
Scientists at the Jean Mayer USDA Human Nutrition Research Center (USDA HNRCA) on Aging at Tufts University and Yale University School of Medicine appear to have discovered a gene responsible for causing weight gain, where the removal of it seems to do the opposite: decreases fat and aging. This gene, called FAT10, plays a role in how much fatty tissue there is in the body and how it affects metabolism. So far, this has only been seen with mice, bit that’s typically one of the last steps before testing in humans. So what exactly does FAT10 do, and how can it be applied to humans?
The Science of Gaining Weight
One of the main reasons we start gaining weight after that magical age of 30 is because our metabolism slows. When this happens, food doesn’t get converted to energy as efficiently, instead resting in our bodies as fat. It takes more exercise to metabolize this food, and increasing our activity isn’t always something that happens when you get older.
Further, our bodies slowly become less pliable and heal slower as we get older, meaning we have to be a bit more careful about throwing ourselves into the body-bending exercises we did when we were younger. Something like sprinting is fine for a young adult, but that constant pounding is hard on the knees and feet (as well as general balance), which are two things that older adults have to be more careful about.
How Adipose Tissue is Linked to Aging
We recently wrote an article about how salt speeds up the aging process, and one of the factors is this: telomeres (the ends of chromosomes responsible for bodily repair — and keeping us looking young) get shorter when they’re inflamed, and when they get shorter, there’s just less of them to help heal our bodies. And when there are less of them to carry out repair work, that means that not everything on the body repair list gets tended to.
Adipose tissue is one thing that can cause inflammation in the body and shorten telomeres, which is a fancy way of saying fatty tissue causes you to age faster on the inside. Although there are many genes and bodily functions associated with weight gain and telomeres in general, the discovery of FAT10 is a particularly ground-breaking one because it very specifically points to one cause.
What is FAT10?
Both mice and humans have around 25,000 genes, all of which act separately and together to do billions of things. Isolating a gene is important because it can possibly tell us exactly what’s going on in the body at a specific time, but what it doesn’t necessarily tell us is that that gene is only responsible for Action X each and every time. Its interaction with other genes can either suppress or stimulate the original gene, which is why studying the body is such a tricky thing.
In terms of FAT10, what it’s responsible for in mice is “coordinating the immune system and metabolism, and deleting the gene in mice reduces body fat and extends lifespan”. It’s important to note that this hasn’t yet been proven to be the same in humans (genes don’t have a one-to-one correspondence in actions in mice and humans), as well as “eliminating FAT10 will not fully address the dilemma of aging and weight gain”.
Along with not knowing if FAT10 is the same in both mice and humans, this is also because of the previous point: genes don’t operate the same way each time, and are affected by many things we still don’t know about. Lab mice live in fairly clean, sterile conditions, whereas we humans gad about in relative filth by comparison.
As well, lab mice, because they live pretty germ-free existences, are more susceptible to catching infections, something which stored fat (which can be converted to energy, as discussed in the first header) is more capable of providing. If mice, which are leaner without the FAT10 gene, can’t fight infection as easily as mice with the gene, would that be the same for humans, too? And if we can’t fight infections as easily without the FAT10 gene, is deleting it really that beneficial for the sake of losing weight and delaying aging?