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What is Myopathy, X-linked, with excessive autophagy and explain in detail?
X-linked myopathy with excessive autophagy (XMEA) is a rare childhood onset disease characterized by slow progressive vacuolation and atrophy of skeletal muscle. There is no known cardiac or intellectual involvement.

Presentation
The incidence of this disease is not precisely known but it is considered to be rare (< 1/106 population). It has been reported in 15 families to date mostly from Canada, Finland and France.This disease usually presents between the ages of 5 to 10 years old. The usual picture is with weakness involving the upper legs and affects activities such as running and climbing stairs. As the condition progresses, patients tend to experience weakness in their lower legs and arms. Some remain able to walk in advanced age, while others require assistance in adulthood.

Genetics
This disorder is inherited in a recessive X linked fashion. As a result, males are much more commonly affected than females. It is due to a mutation in VMA21 gene - the human homolog of the yeast Vma21p protein