Redheads might have a better excuse than the rest of us for avoiding the dentist.
For several years now scientists have known that the same genetic variations that give redheads their fiery manes can increase the amount of general or local anesthetic a person needs in order to be properly put out or numbed up.
New research suggests that the effect of these variations is strong enough, and hasn’t been addressed by dentists well enough, that the people who carry them are more than twice as likely as those who don’t to avoid going to the dentist altogether.
Researchers at the University of Kentucky surveyed 67 redheads and 77 dark haired people about their general anxiety levels, their dental treatment-related anxiety and their fear of dental pain. The results, published in the July issue of the Journal of the American Dental Association, reveal that while hair color has no effect on general anxiety, redheads are more likely to be apprehensive about sliding into the dentist’s chair.
A closer look at the data showed that increased dental-treatment anxiety and fear of dental pain is found in all people with the variants in the MC1R gene associated with red hair, even those people who carry these variations despite having dark hair.
The protein encoded by the MC1R gene is found in melanocytes, the cells that give hair and skin their color. The variants associated with red hair alter the protein’s function, tipping the balance of pigment production in melanocytes from black-brown eumelanin to red-yellow pheomelanin. Researchers don’t yet understand how this same protein impacts pain sensitivity and anesthetic needs.
People carrying one or two of the MC1R variants had 2.46 times greater odds of avoiding routine dental care compared to those who carry none. The authors speculate that this might be because prior dental experiences have left them in pain.
(23andMe customers can use the table at the end of this post to see if they carry any of the MC1R variants associated with dental treatment-related anxiety, fear of dental pain and avoidance of dental treatment.)
The researchers recommend that dentists evaluate all patients, especially those with natural red hair, for dental procedure-related anxiety and take whatever steps are necessary to help them manage their feelings and make it to their regular check-ups, because as the saying goes, “Ignore your teeth and they’ll go away.”
| SNP | “Red Hair” Version | Alternate Name For Mutation |
|---|---|---|
| rs34474212 | C | S83P |
| rs1805006 | A | D84E |
| rs11547464 | A | R142H |
| rs1110400 | C | I155T |
| rs1805007 | T | R151C |
| rs1805008 | T | R160W |
| i3002507 | C | D294H |
I don’t seem to have any of those mutations and yet my brother and I both have red hair. I can attest to the fact that I am very difficult to numb in the dental office. I don’t even bother most of the time anymore. It is easier to take the few second pain than having them jab me over and over to get me numb.
I just wanted to add that I have read additional research (cannot locate my original source) that the MC1R Gene is associated with “Rapid Metabolism” of local analgesics. My very read headed, dental avoidant, husband recently had a skin lesion removed. Remembering the rapid metabolism theory, I requested that the doctor use extra and check after 1 minute instead of 10 for numbness. Between throwing away the syringe, and changing into sterile gloves– he was completely numb. Its worth trying if you have problems with getting numb regardless.
I have red hair and have two of the non-red-hair mutation for each of these except the last two, where I have one of each. Still can’t figure out where this red hair is coming from!