Genetic study identifies new form of congenital muscular dystrophy

This discovery will allow a precise genetic diagnosis for a greater number of children affected by this condition, and help inform better clinical management.

The study, led by Dr Yalda Jamshidi from St George’s, University of London and Dr Chiara Manzini from George Washington University, examined the DNA of five individuals who were affected by early onset of a group of conditions including muscle weakness and an inability to stand or walk.

Other symptoms included cataracts, intellectual disability and short stature.

Although some of the symptoms varied between individuals, the results identified mutations in the same disease gene. Mutations in this gene – INPP5K – had not previously been reported.

Zebrafish trials

To get a better idea of the gene’s role in development the researchers blocked the expression of the gene in zebrafish. They found that the fish then showed muscle damage and eye defects, similar to the features seen in the individuals with the mutations.

Congenital muscular dystrophy (CMD) is a term used for a group of genetic muscle-wasting conditions, in which the symptoms become apparent at an early age. They cause muscles to weaken and waste over time, leading to increasing disability. They can also cause learning difficulties.

Robert Meadowcroft, Chief Executive of Muscular Dystrophy UK, commented, “Early stage research identifying genes for muscle-wasting conditions, such as this, gives us valuable insight into better understanding these complex and rare conditions.

Families find it extremely difficult living in limbo without a precise diagnosis, particularly in this current era of increasing precision medicine. The results from this paper could help some families living with congenital muscular dystrophy to receive a faster diagnosis, paving the way for a potential treatment for this mutation in the future.”