Your DNA controls everything about you, and small changes in it can lead to really big changes in things like strength and speed. Here, Hank Green talks about three genetic mutations that allow certain people to have superhuman abilities. [Scroll down for video]
1. Mutation in the gene MSTN – Gives you huge boost in muscle mass and strength without doing any of extra strenuous workouts
Different molecules affect how your muscle tissue grows, including your skeletal muscles. And myostatin – (a protein) – is one of these molecules, and it’s put together from the instructions in a gene known as MSTN. Myostatin limits muscles growth, and it ensures your muscles do not grow too large. However, one mutation in the MSTN gene changes the way the gene’s instructions are used to make myostatin – either causing the gene to stop making myostatin molecules or to stop making proteins that work.
Without myostatin, your muscle tissues will grow bigger and divide way more than usual – giving you a huge boost in muscle mass and even more strength without doing any of vigorous workouts. Moreover, this mutation has also been found to cause myostatin-related muscle hypertrophy, a condition where people (and even children) can look like extra-ripped bodybuilders; and it doesn’t even cause any health problems in affected individuals.
2. Mutation in the gene ACTN3 – Boosts muscle endurance, giving you bursts of power and speed
You have a gene called ACTN3 (aka the sports gene), and there’s a protein in skeletal muscles called alpha-actinin-3, which is encoded by it. Alpha-actinin-3 controls fast-twitch muscle fibers – muscle cells that have quick contraction times and give you bursts of force. They help you sprint really fast.
Well, if we all have this gene, why can’t we all sprint like Usain Bolt? Turns out, most of us have a loss-of-function mutation in the ACTN3 gene, so we don’t have working alpha-actinin-3 proteins. Researchers say some elite sprinters and power athletes have at least one functional copy of this gene.
3. Mutation in the gene LRP5 – Increases bone strength and bone becomes practically unbreakable
Gene LRP5 regulates bone mineral density, and is known to be a part of the Wnt signaling pathway – a signalling pathway that affects the way cells and tissue develop. A mutation in this gene cause the protein “low density lipoprotein receptor-related protein 5” to kickstart certain signaling pathways on your bone cells, making them grow denser and bulkier—conditions that are generally called osteosclerosis and hyperostosis.
Anyone with this mutation don’t have to worry about breaking an arm or fracturing their skull as sometimes the mutation causes the bone to become practically unbreakable. Also, the same type of mutation can cause “too much hyperostosis”, which can lead to really severe forms of bone growth, like where your skull puts pressure on your brain, or your bones pinch your nerves, explains Hank in the video.