Expanding the phenotypic and imaging spectrum of GFPT1-related congenital myasthenic syndromes: a Brazilian case series

GFPT1-related congenital myasthenic syndrome (CMS) is a rare, autosomal recessive disorder that impairs neuromuscular transmission due to defective glycosylation of the neuromuscular junction. While typically presenting with limb-girdle weakness, tubular aggregates on biopsy, and a favorable response to acetylcholinesterase inhibitors, the full phenotypic and imaging spectrum remains incompletely defined. We evaluated five Brazilian patients from two unrelated families, all with pathogenic variants in homozygosity in GFPT1 c.41G>A (p.Arg14Gln).