Author: Mohammad Faour, Yr 12
The myostatin gene is a growth factor which regulates the muscle mass that mammals can put on. This recessive gene inhibits the production of a protein which controls muscle development and prevents it from growing too large. Myostatin is known as Growth differentiation factor 8 (GDF-8). This means its responsible for controlling the growth of muscles tissue.
The human body has a subfamily of proteins known as growth differentiation factors (GDF). Which belong to the transforming growth factor-beta superfamily (TGF-beta) These factors, numbered 1-15, play a vital role in the development of the human body. For example, GDF-5 is involved in several developmental processes including, cartilage development, limb generation, joint formation and cell survival. Since myostatin is a myokine, it acts on the muscle cells function to inhibit myogenesis: muscle fibre growth. Myostatin works by blocking activin type II receptors which halts the production and growth of muscle cells. These type II receptors are proteins found in the cell membrane, which allow nutrients to be transferred to the cell. Blocking this receptor stops the nutrients from entering; therefore, muscle growth stops. This protects the body from building too much muscle mass. If the body gains too much muscle, it can cause strain on the person's organs and their skeletal structure.
A mutation of the myostatin gene limits the amount of myostatin produced by the body. Which then allows for more muscle hypertrophy as the receptors can keep taking in nutrients to help with muscle hypertrophy. The most common cases of the mutation are in the Belgian blue cows. The mutation causes the cow to have an extremely muscular physique known as double-muscling. The double muscling phenotype is inherited by the parents and causes extreme muscle hypertrophy. It also causes the cow's body to have less fatty deposits resulting in lean meat with low fat to muscle ratio. This increase in muscle amounts to over 40% more muscle in adults and double the amount of muscle in calves. The skeletal build of the cow is the same in cows without the mutation. This causes strain on the cows and is seen to reduce the lifespan of some cows.
Although the mutation is common in some animal breeds, it is rare to find in humans. The first reported case of the mutation was in 2007. However, the most well-known case is the former Worlds Strongest Man Eddie hall. Scientists says that due to his mutation, he has been able to build more muscle, particularly type IIx, which allows him to lift such heavyweights. Due to him being a living example of its benefits, scientists have been researching how to use this mutation to treat certain diseases. There have been recent studies which been focusing on using myostatin signaling pathways to mitigate muscle loss in diseases such as cancer, chronic kidney or heart failure. The muscle loss that the patient's experience has a significant impact on their mortality rate. The muscles loos leads to a lack of activity and leads to the loss of essential proteins. Drugs to counteract muscle loss can lead to a breakthrough when treating chronic diseases. However, scientists are in the early stages in developing a drug for this.
The mutation in the myostatin gene has proved to have many benefits in humans as well as animals. However, since the research needed is still in early stages, it can cause issues that cannot be anticipated.
Comments