Advances in the pathophysiology of myoglobinopathy

Myoglobinopathy is an ultra-rare autosomal dominantEn génétique, c’est la caractéristique d’un individu qui n’a besoin que d’un seul exemplaire d’un certain gène (allèle) pour s’exprimer. Cet exemplaire unique peut venir du père ou de la mère. neuromuscular disease first described in 2019 and caused by a His98Tyr mutationModification soudaine et transmissible du matériel génétique. Elle peut être spontanée ou induite par des agents dits » mutagènes » (radiations, produits toxiques,…). in the MB gene that encodes myoglobin. Myoglobin is the muscle equivalent of hemoglobin. It is used to store oxygen, to ensure its diffusion in the heart and muscles, and would protect the muscle cell against free radicals. Italian researchers performed comparative functional studies to better understand the deleterious effects of the previously reported His98Tyr mutation. According to their results: 

• the architecture varies little between the two forms of myoglobin, mutated and non-mutated; 
• mutated myoglobin tends to form protein aggregates;
• it is also more sensitive to the effects of free radicals and does not retain oxygen well.

Pseudoperoxidase activity, conformational stability, and aggregation propensity of the His98Tyr myoglobin variant: implications for the onset of myoglobinopathy. Hofbauer S, Pignataro M, Borsari M, et al. FEBS J. 2021 Oct 22.