Cause I'm a Muscle Man...

After complaining about something stupid in my local paper, I find something cool.

(AP) Mutation Found in ‘Muscle Man’ Toddler

This is a AP report on a discovery reported recently in the NEJM. Apparently, a German boy was born with a pair of genetic mutations that block myostatin production. Myostatin is a negative control on muscle growth. Thus this child who is not yet five has adult level strength. Since I haven’t had time to grab the actual report, I assume that the actual mutations are loss of function mutation. Instead of “blocking” the action of myostatin as report indications, these mutations probably cause myostatin production to be broken. But, like I said I haven’t read the paper.

Some interesting sections from the AP report.

Researchers would not disclose the German boy's identity but said he was born to a somewhat muscular mother, a 24-year-old former professional sprinter. Her brother and three other close male relatives all were unusually strong, with one of them a construction worker able to unload heavy curbstones by hand.

In the mother, one copy of the gene is mutated and the other is normal; the boy has two mutated copies. One almost definitely came from his father, but no information about him has been disclosed. The mutation is very rare in people.

This seems to indicate that the concentration of myostatin an important part of its activity. An immediate impact on human evolution is to potentially explain the difference in strength between humans and our relatives. One obvious hypothesis is that chimps produce less myostatin than humans, thus causing them to have higher muscle mass. I also would not be surprised if testosterone somehow represses myostatin, which would explain how the hormone promotes muscle mass.

The actual paper is:


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Sent by Pharyngula on June 24, 2004 6:41 PM

Reed Cartwright has a comment on this fascinating human mutation that increases muscle mass: (AP) Mutation Found in ‘Muscle Man’ Toddler This is a AP report on a discovery reported recently in the NEJM.  Apparently, a German boy was born with a pa... [Read More]

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