HIV. One patient in South Africa was identified who produced HIV-neutralizing antibodies following infection. This discovery points to a potential “Achilles heel” within the virus, and provides the groundwork for the potential development of future anti-HIV vaccines.
The phrase “treasure your exceptions” is well known in the genetics community. It was coined and popularized by English geneticist William Bateson (1861-1926), who was also the first person to use the term “genetics.” In its original context, “treasure your exceptions” was used to point out the value of analyzing unusual traits in various living organisms. This type of work was being done in Gregor Mendel’s breeding of pea plants (being tall or short), Thomas Hunt Morgan’s study of fruit flies (having red or white eyes), and William Castle’s analysis of the coat colors of mice.
Most genetic differences are initially revealed because they have an unusual phenotype (essentially, the physical appearance of an organism). In the real world, not all mutations lead to X-ray vision, give one the ability to fly, or produce claws made of “adamantium” steel. However, there are a number of recently discovered mutations that have given people super strength, invulnerability, and tremendous endurance, all abilities that would make the X-Men proud. The following stories were all nicely told in David Epstein’s book, The Sports Gene: Inside the Science of Extraordinary Athletic Performance.
Super Strength – The trait was first identified in Belgian Blue cattle, which have twice the muscle mass as regular cattle. Molecular analysis of their muscle tissue revealed mutations in a gene encoding the protein myostatin, which normally regulates muscle growth. These mutations lead to a failure to stop muscle growth, which is part of the normal process. As a result, myostatin mutations are associated with extreme musculature, which translates into great strength and, in some situations, great speed. Distinct mutations in this gene in thoroughbred racehorses can be used to predict a horse’s success as a sprinter or a long distance runner. The first human identified with myostatin mutations was a baby born in Germany in 2004; at birth he already had well developed muscles. There are worries that these mutations will negatively affect his heart muscle as well, but so far no developmental problems have been noted. Drugs that modulate myostatin levels or activity have been put into clinical trials in an effort to restore muscle strength in boys with muscular dystrophy, but none so far have proved effective.
Invulnerability – A family was identified in Pakistan whose members felt no pain. They have a mutation in the SCN9A gene, which encodes a type of sodium ion channel. The mutation blocks the pathway that nerve signals take on the way to your brain, and as a result, these individuals feel no pain. Despite what many of us might think, this mutation is no blessing. People afflicted with this mutation tend to die at a young age. This is because they either get seriously injured but don’t seek treatment (pain is nature’s way of telling you it’s time to go to the doctor), or because they don’t continuously shift their weight as the rest of us do (even while sleeping), and this leads to joint infections that eventually prove fatal.
Great Endurance – Mutations in the gene encoding the erythropoietin receptor turned out to be responsible for Eero Mäntyranta’s cross county skiing prowess. Dubbed “the Flying Finn,” and blessed with tremendous endurance, he won medals in the 1960, 1964, and 1968 Olympic Winter games. His victory margin in the 15K race in 1964 was 40 seconds, a margin that has never been bested. Analysis of his DNA revealed that his erythropoietin receptor is truncated compared to other people. As a result, it is overly sensitive to erythropoietin and naturally leads to the overproduction of red blood cells in his system. Having more red blood cells means greater oxygen carrying capacity, which in turn translates into great endurance. Modern blood dopers (e.g. Lance Armstrong) have injected themselves with erythropoietin to accomplish the same task.
The genetic traits identified above, as far as I know, have not led to the affected individuals being ostracized from their communities for being “different,” an event that the X-Men experienced all too often. The Genetic Information Nondiscrimination Act (GINA) of 2008 bars employers from demanding genetic information from employees, and prevents employers and health (but not life, disability, or long-term care) insurance companies from discrimination based on your genetic information. Even with this limited protection, many question the wisdom of having one’s genetic information made publicly available. The identification of people based solely on their DNA sequences has unfortunately turned out to be much easier than previously thought.
The X-Men stories began only 10 years after the discovery of the structure of the DNA double helix in 1953, and DNA sequencing didn’t arrive until the 1970’s. Tales of the X-Men were published in Marvel Comics; reports about interesting mutations in people these days are more likely to show up in journals like Cell, Science, and Nature. The Marvel focus was not on uncovering the genetic underpinnings behind the remarkable powers with which these individuals were endowed. Of greater interest to the writers was dramatizing the way these people were shunned by society for simply being “different,” a recurrent theme in the comic book industry since its early days. It’s part of a continuing commentary on our society where many people (both in comics and in real life) are often ill treated because they’re part of some minority group. These differences, whether in race, sexual orientation, or appearance sometimes evoke fear in the uninformed. As Marie Curie said, “Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.” UCB’s Innovation Challenge may help to do just that in a way that will bring health benefits to all of us.
