Phenotypic variability in siblings with type III spinal muscular atrophy

• Published in: Journal of neurology, neurosurgery and psychiatry Vol. 75; no. 12; pp. 1762 - 1764
• Main Authors: Muqit, M M K, Moss, J, Sewry, C, Lane, R J M
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd 01.12.2004; BMJ; BMJ Publishing Group LTD; BMJ Group
• Subjects: Adolescent; Atrophy; Biological and medical sciences; Biopsy; Child, Preschool; Cyclic AMP Response Element-Binding Protein; Denervation; Diseases of striated muscles. Neuromuscular diseases; Genes; genetics; Genotype & phenotype; Humans; Injuries of the nervous system and the skull. Diseases due to physical agents; Kinases; Male; Medical prognosis; Medical sciences; Muscle Weakness - pathology; Muscular Atrophy; Mutation; myopathy; Nerve Tissue Proteins - genetics; Neurology; Patients; Phenotype; Phosphatase; Proteins; RNA-Binding Proteins; Short Report; Siblings; SMA; SMN; SMN Complex Proteins; Spinal Muscular Atrophies of Childhood - genetics; Spinal Muscular Atrophies of Childhood - pathology; spinal muscular atrophy; Stains & staining; survival motor neurone; Traumas. Diseases due to physical agents; Tremor; Weightlifting; Neuromuscular diseases; Nervous system diseases; Variability; Central nervous system disease; Spinal amyotrophy; Degenerative disease; Sibling; Spinal cord disease
• ISSN: 0022-3050; 1468-330X
• DOI: 10.1136/jnnp.2003.018614

Autosomal recessive spinal muscular atrophy (SMA) shows substantial phenotypic variability, presenting at a variety of ages from infancy to adult life. Diagnostic difficulties may arise because SMA sometimes produces a dystrophic or myopathic phenotype rather than classical neurogenic abnormalities. Two brothers are described who illustrate this principle and highlight the increasing importance of molecular genetics in investigating patients with neuromuscular diseases. The findings are discussed in the light of recent observations in a mouse model of SMA.