Molecular genetic study of a childhood form of spinal muscular atrophy.
Molecular genetic studies were performed in 28 cases of childhood-onset spinal muscular atrophy (24 unrelated families). This consisted of type 1 (severe) (n = 5), type 2 (intermediate form) (n = 8), and type 3 (mild) (n = 15). Deletion of exons 7 and 8 of the SMNt gene was found in 100%, 100%, and 93%, respectively, in type 1, 2, and 3 spinal muscular atrophy. Deletion of exons 5 and 6 of the NAIP gene was found in 3 of 5 (60%) of type 1 and none of the type 2 and 3 cases. None of the 32 asymptomatic relatives had homozygous deletions in the SMNt and NAIP genes. Thus, the role of the NAIP gene needs to be specifically defined in spinal muscular atrophy. In a suspected case of spinal muscular atrophy, deletion of the SMNt gene is a useful laboratory marker for confirmation of the diagnosis.
Wong
V
V
Department of Paediatrics, Queen Mary Hospital, Faculty of Medicine, The University of Hong Kong. VCNWONG@hkucc.hku.hk
Chan
V
V
D000293:Adolescent; D000328:Adult; D005260:Female; D017353:Gene Deletion; D006801:Humans; D008297:Male; D009134:Muscular Atrophy, Spinal / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D051616:Neuronal Apoptosis-Inhibitory Protein; D010375:Pedigree
C496800:NAIP protein, human; D009419:Nerve Tissue Proteins; D051616:Neuronal Apoptosis-Inhibitory Protein