A question from Tyler, location unknown:
"My question is a bit complicated, so please bear with me.  I'm a male redhead who was diagnosed with Malignant Hyperthermia (MH). I was apparently diagnosed the hard way when I was about 1yr old after a relatively minor surgery, and then spent the next week in a bubble.
I've always run a little hot, always had a high metabolism, and have always had a really high tolerance for medication. Is it possible that there is a link between my MH and my metabolism? Would it also be possible that there's a link to my tolerance for pain medication and others?"

Dear Tyler,

Thanks for your question. I don't think these conditions are linked to each other, per se, but rather linked to your particular genetics and ancestry. It could be that by random chance, you have several different genetic mutations that cause these 3 conditions (MH, red-headed-ness, and "running hot"). I am going out on a limb here and guessing that since you are a redhead, you are of northern European descent (Scottish, Irish, Scandinavian, etc.) and your ancestors haled from a cold climate. 

Malignant hyopthermia, as you already know, runs in families and is linked to genetic changes in several genes (see this link). For my other readers' benefit, MH causes a fast rise in body temperature and severe muscle contractions when someone with this disease is administered general anesthesia. It can be life threatening. This is, unfortunately, something that runs in your family. These are genes located in your 46 "normal" chromosomes.

It turns out that people from colder climates may tend to have mutations in mitochondrial DNA (mtDNA) which modify the electron transport system, leading to excess heat production rather than adenosine triphosphate (ATP) production. ATP is the currency of energy in our cells, but mitochondria also produce heat, part of the metabolic system which allows us to maintain constant body temperature. These mtDNA mutations in some northern people are like the difference between a well-oiled drive chain or conveyor belt producing very little heat when it moves, versus an un-oiled rusty drive belt squealing and heating up as it turns. You've got the rusty drive belt, my friend. This was advantageous for humans living in colder climates. It burns more calories but also keeps your body warmer (see link to Science Daily article to start). It could be that these mitochondrial gene mutations tend to make MH more severe for you, unfortunately, as your body has difficulty cooling itself.

And finally, redheaded traits are caused by mutations of the melanocortin-1 receptor gene (MC1R). It turns out that anesthetic resistance is significantly increased in redheads (see link). This is pretty well known among doctors and dentists, as once a dentist offered me extra local anesthetic before working on my fillings (I had dyed my hair red at the time). Redheads experience reduced efficacy of lidocaine, a local anesthetic used by dentists (see link). This may not be related to the actual red hair, it may be that the genes which regulate anesthetic drug metabolism, and other drug metabolism, are directly or indirectly linked to the genes which control complexion and hair color. 

Advantages: If lost in a snowstorm or exposed to extreme cold, you will do better than other people to avoid hypothermia and frostbite. Also, I bet you can eat a lot of food and not gain weight. Unfortunately, you also suffer from MH when needing to undergo surgery. I wish you my best for safety and health.