Limb Girdle Muscular Dystrophies (or LGMD) constitute a very heterogeneous group of neuromuscular diseases both clinically and genetically. Their nomenclature underwent a major revision in 2018 to better take into account their genotypic diversity. LGMDs have in common an impairment of the musculature proximal to the pelvic and scapular girdles and evolve in a very varied way. Mutations in 28 different genes are currently responsible for forms transmitted in an autosomal recessive mode, some of which are extremely rare.
In an article published in October 2019, an international consortium of researchers reports five new observations of patients with LGMD R26 confirming the involvement of the POPDC3 gene. These cases were identified following whole exome analysis of 1,500 people with limb girdle weakness or hyperCKemia with no molecular signature. The clinical and biological data of the five people affected and from three unrelated families were analyzed. The clinical phenotype, including imaging, presented a classic picture of LGMD, without cardiac involvement. Functional studies carried out in zebrafish and Xenopus show that inhibition of the popdc3 gene leads to muscular dystrophy.
