myopathy with lactic acidosis and sideroblastic anaemia type 2

myopathy with lactic acidosis and sideroblastic anaemia type 2

A rare skeletal muscle- and bone marrow-specific oxidative phosphorylation disorder (OMIM:613561), which is characterised by sideroblastic anaemia, progressive lethargy, muscle weakness, and exercise intolerance associated with persistent lactic acidaemia. 

Molecular pathology
Caused by defects in YARS2, which encodes a mitochondrial protein that catalyses the attachment of tyrosine to tRNA.