NIH Rare Diseases

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.Orpha Number: 2598Disease definitionMitochondrial myopathy and sideroblastic anemia belongs to the heterogeneous family of metabolic myopathies. It is characterised by progressive exercise intolerance manifesting in childhood, onset of sideroblastic anaemia around adolescence, lactic acidaemia, and mitochondrial myopathy.EpidemiologyLess than 10 cases have been described so far.EtiologyA 656C-->T mutation in the nuclear pseudouridine synthase 1 gene (PUS1), localised to 12q24.33, has recently been identified in some patients. Deficient pseudouridylation of mitochondrial tRNAs may be responsible for the oxidative phosphorylation disorder.Diagnostic methodsMuscle biopsy demonstrates low activity of complexes 1 and 4 of the respiratory chain and paracrystalline inclusions can be revealed in most mitochondria by electron microscopy.Genetic counselingTransmission is autosomal recessive.Visit the Orphanet disease page for more resources. Last updated: 6/15/2006

MalaCards based summary

Myopathy, Lactic Acidosis, and Sideroblastic Anemia 1, also known as mitochondrial myopathy and sideroblastic anemia, is related to sideroblastic anemia and mitochondrial myopathy, and has symptoms including high palate, intellectual disability and muscular hypotonia. An important gene associated with Myopathy, Lactic Acidosis, and Sideroblastic Anemia 1 is PUS1 (Pseudouridylate Synthase 1), and among its related pathways/superpathways is Aminoacyl-tRNA biosynthesis. Affiliated tissues include bone, bone marrow and skeletal muscle.

OMIM

Myopathy, lactic acidosis, and sideroblastic anemia (MLASA) is a rare autosomal recessive oxidative phosphorylation disorder specific to skeletal muscle and bone marrow (Bykhovskaya et al., 2004). (600462)

UniProtKB/Swiss-Prot

Myopathy with lactic acidosis and sideroblastic anemia 1: A rare oxidative phosphorylation disorder specific to skeletal muscle and bone marrow. Affected individuals manifest progressive muscle weakness, exercise intolerance, lactic acidosis, sideroblastic anemia and delayed growth.