J.Andoni Urtizberea - Institut de Myologie, APHP, Filnemus PARIS – France

Most neurologists, paediatricians and medical geneticists know about thetypical presentations of spinal muscular atrophy (SMA). And more specifically,the ones related to the 5q-linked autosomal recessive form of SMA likeWerdnig-Hoffmann disease or Kugelberg-Welander disease. SMA actuallypresents with different degrees of severity and motor achievements which arenot always easy to categorize clinically into the four reported subtypes (type 1to type 4) suggesting a continuum of phenotypes.Easier access to confirmatory testing of the SMN1 gene and nowadays to NGSstudies (high-throughput sequencing of a myriad of genes) recentlyhighlighted the existence of many non-5q related forms of SMA. Althoughquite rare taken individually, these variants are important to recognize sincetherapeutic options and genetic counselling vary from one syndrome toanother.Among those, Brown-Vialetto-Van Laere syndrome (BVVL) and Fazio-Londesyndrome, two forms of severe childhood bulbospinal muscular atrophy withand without associated sensorineural deafness related to mutations in tworiboflavin transporters genes, are amenable to a cheap, effective therapybased on oral supplementation of high-dose riboflavin (vitamin B2, 30mg/kg/d).