Can Be Homozygous or Can Be Compound Heterozygous
CMT2X is caused by autosomal recessive mutations in the SPG11 gene. Other mutations in this gene are associated with causing a condition called Spastic Paraplegia Type 11, or SPG-11 (OMIM 604360), hence the gene’s name; and other mutations in this gene are associated with causing Juvenile ALS Type 5 (OMIM 602099). These mutations are unique to these conditions and are separate from the mutations in the gene that are associated with causing CMT2X.
CMT2X symptoms can start to occur anywhere between early childhood and early adulthood. Symptoms and symptom severity can vary widely. CMTers who have CMT2X usually will experience lower leg, foot, and ankle weakness, atrophy, and sensory loss, as well as the same in the upper legs. Many CMTers who have CMT2X will also experience the same in the arms and hands. Additionally, many CMTers who have CMT2X will experience frequent fasciculations (random and frequent muscle twitches just beneath the skin) in their upper legs.
Some CMTers who have CMT2X might also experience bladder dysfunction, bowel dysfunction, and/or sexual dysfunction. Some might experience mild to moderate cognitive impairment also.