The experience of a French Neuromuscular Disease Reference Centre with patients suffering from collagenopathy

Analysis of the genetic and clinical data from a cohort of 25 patients, children and adults, with defects in the collagen VI (COL6A1-3) genes and followed up at the Marseille Neuromuscular Disease Reference Centre in France showed that :

• 5 had Ullrich-type muscular dystrophy, 15 had Bethlem myopathy and 5 had an intermediate form;
• 14 patients had an autosomal recessive form caused by 8 different pathogenic variants and 11 an 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. form caused by 8 other variants;
• the most common variant (c.1970-9G>A in the COL6A2 gene) affected 29% of patients;
• three of the pathogenic variants identified had not previously been described in the literature;
• in a sub-group of patients, the disease progressed more rapidly, with loss of walking in childhood, unrelated to a specific variant.

Retrospective clinical and genetic analysis of COL6-RD patients with a long-term follow-up at a single French center. Morel V, Audic F, Tardy C et al. Front Genet. 2023 Dec.