Some With Autism May Have Muscle Weakness

Some children with autism may have a genetic defect that affects their muscles, a small U.S. study indicates.

Study author Dr. John Shoffner, owner of Medical Neurogenetics, LLC in Atlanta, studied 37 children with autism spectrum disorders who were evaluated for mitochondrial disease, which causes muscle weakness and prevents a child from being able to participate in physical activities and sports. Mitochondrial disease occurs when genetic mutations affect the mitochondria, or the part of the cell that releases energy, Shoffner explained.

The study found that 24 of the children, or 65 percent, had defects in the process by which cells produce and synthesize energy in the muscles, or oxidative phosphorylation defects in the skeletal muscles.

Most children with autism spectrum disorders do not have recognizable abnormalities when you look at genetic tests, imaging and metabolic tests, Shoffner said in a statement. But a subset of these children does have significant defects in this area. Identifying this defect is important for understanding how genes that produce autism spectrum disorders impact the function of the mitochondria.

The findings are to be presented at the American Academy of Neurology 60th anniversary annual meeting in Chicago.