Mutant Fish Sheds Light on Rare Disease

A mutant zebrafish that came into scientist’s cross hairs over 20 years ago, has similar symptoms as patients who suffer from nemaline myopathy. This highly rare genetic muscle disorder is characterized by muscle weakness, deflated muscle tone, and reduced or absent reflexes. To learn more about nemaline myopathy, click here.

A recent study details the poor motor functions typical in patients who have mutations in this gene, like the zebrafish. They experimented first on mice but could not get accurate data because mice embryos die before their skeletal muscles have developed.

As Philip Ingham, head of the Developmental and Biomedical Genetics Laboratory at the A*STAR Institute of Molecular and Cell Biology, said:

“The zebrafish mutant provides the only animal model for studying the effects of the myo18b mutation on skeletal muscle.”

Ingham, along with his team of postdoctoral fellows in Singapore and England, worked diligently to identify a strain of mutant zebrafish that were discovered by German researchers in the late 90’s. These researchers had been searching for a gene mutation that affected the motility of these fish. What they learned was that fish embryos lacked fast-twitch muscle fibers which are needed for regular movement. However, they didn’t know exactly where the gene was located within the zebrafish’s genome.

Since then, Ingham and company have completed the work that the German researchers left off. Using genetic markers and fish breeding experiments, they learned that the zebrafish was 50 percent identical to its human counterpart, which was then linked to the rare genetic muscle disorder of nemaline myopathy.

Written analyses of the zebrafish was enough evidence to prove that a specific motor protein is necessary for regular skeletal muscle development, which is also the case for nemaline myopathy patients.

Ingham believes that the fish can serve as a model to better understand nemaline myopathy and hopes that scientists can use this as a way to treat it with future patients.