anaemia sideroblastic pyridoxine-refractory autosomal recessive
Definition A form (OMIM:205950) of sideroblastic anaemia* which is unresponsive to pyridoxine.
*Sideroblastic anaemia is characterised by anaemia of varying severity, hypochromic peripheral erythrocytes, systemic iron overload due to chronic ineffective erythropoiesis, and ringed sideroblasts in the bone marrow. Sideroblasts are iron-loaded mitochondria clustered around the nucleus.
Molecular pathology Defects of
• GLRX5 (OMIM:609588), which encodes a mitochondrial protein required for normal iron homeostasis and
• SLC25A38 (OMIM:610819), which encodes a protein required during erythropoiesis for haem synthesis, both cause anaemia—sideroblastic—pyridoxine-refractory—autosomal recessive