DE-NOVO FACIOSCAPULOHUMERAL MUSCULAR-DYSTROPHY DEFINED BY DNA-PROBE P13E-11 (D4F104S1)

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant condition with variable age of onset and severity. Identification of a de novo DNA fragment by probe p13E-11 (D4F104S1) established the dia gnosis of new mutation FSHD in 27 of 31 sporadic cases. The clinical d ata for these certain new mutation cases were as follows: 13 boys, 14 girls; mean age of onset 6.8 years; significant leg weakness in 19/27 (70%) (8/27 (30%) used wheelchairs at a mean age of 17.7 years); high tone sensorineural deafness in 10/27; visual acuity and direct ophthal moscopy were normal. Congenital facial diplegia and sensorineural deaf ness in three children suggest that infantile FSHD is not a geneticall y separate disorder from FSHD. Ascertainment bias may explain the diff erence in severity between this group and typical familial cases. Mole cular analysis for FSHD should be considered in children with either c ongenital or early onset facial weakness or diplegia.