Families

The COQ4gene contains the instructions for a protein that cells need to make coenzyme Q10 (CoQ10). CoQ10 helps the "power plants" of the cell (the mitochondria) to produce energy. When both copies of the COQ4gene contain a mutation, the body cannot make enough CoQ10 and organs that need a lot of energy, especially the brain, muscles and heart, can be affected.

The condition is very rare and its severity differs greatly from person to person. Some babies are very severely affected from birth, with problems of the heart, breathing and seizures. Other children or adults have a much milder condition, with slowly increasing balance problems (ataxia) and stiffness of the legs. The condition is inherited in an autosomal recessive way: both parents carry one changed copy of the gene without having the disease themselves, and each future pregnancy has a 25% chance of a child with the condition.