Why do some guys go grey in their 20s, while others reach their 40s without a single silver strand in sight? We know that genetics play a role in the greying process, but scientists still haven’t pinpointed the exact reason some guys become silver foxes before others. A study published in the journal PLOS Biology may bring us one step closer to an answer. According to the new research, a gene that helps regulate our immune systems also helps regulate hair colour. The study was conducted on mice, but it may eventually help explain why guys go grey when they do. According to Gizmodo, study co-author Melissa Harris a biology professor at the University of Alabama at Birmingham decided to study melanocyte cells in lab mice to better understand aging (we lose these cells as we get older). Her team studied one particular gene found in melanocyte cells: melanogenesis associated transcription factor, or MITF. The gene helps control the production of melanin. First, the researchers looked at mice that were bred to go grey early and found that these guys created a lot of the MITF gene. Harris theorised that more MITF decreased the number of melanocyte cells therefore creating less melanin. Less melanin means more grey hair. They also engineered mice to make less of the MITF gene, thinking it would slow the greying process but they were surprised to find the mice went grey just as quickly. Though puzzled at first, Harris team discovered that mice with small amounts of the MITF gene had more of a protein found in the immune system called interferons. Interferons help your body protect against invaders like cold and flu viruses. Essentially, higher levels of the MITF gene were associated with lower levels of interferon proteins. The researchers concluded that when there were too many interferons, the mice’s immune systems didn’t know how to behave and attacked melanocyte cells instead of just foreign viruses. It’s not clear whether having more of the MITF gene decreased the interferons, or whether having more interferons decreased the MITF gene levels. We simply know there could be a relationship between the immune system and a gene that contributes to our hair colour. Of course, this is just a starting point for more research on the link between the immune system and grey hair. The researchers say their findings may also help explain other conditions involving pigmentation, like vitiligo. For now, you’ll just have to rely on hair dye or own those greys like Clooney.
Popular Mechanics, 6 May 2018 ; https://www.popularmechanics.com