6533b860fe1ef96bd12c3acf
RESEARCH PRODUCT
A Paucisymptomatic Neuromuscular Disease Mimicking Type III 5q-SMA With Complex Rearrangements in the SMN Gene
Laura Nanna LohkampKarin DrosselBrunhilde WirthUlrike GriebenWolfram KressWerner StenzelLutz GarbesFrank L. HeppnerKatja Von AuHans-hilmar GoebelHans-hilmar Goebelsubject
MalePathologymedicine.medical_specialtyNeuromuscular diseaseBiopsyDNA Mutational AnalysisSMN1Spinal Muscular Atrophies of ChildhoodBiologyQuadriceps MuscleDiagnosis DifferentialMice03 medical and health sciencesExonAtrophyGene duplicationmedicineAnimalsHumansChildSequence Deletion030304 developmental biology0303 health sciences030305 genetics & heredityNeuromuscular DiseasesSpinal muscular atrophymedicine.diseaseSMA*ImmunohistochemistrySurvival of Motor Neuron 1 ProteinMolecular biologynervous system diseasesSmn geneSurvival of Motor Neuron 2 ProteinMuscular AtrophyPhenotypeMutationPediatrics Perinatology and Child HealthNeurology (clinical)description
Spinal muscular atrophy is an autosomal-recessive neuromuscular disorder, causing progressive proximal weakness and atrophy of the voluntary muscles. More than 96% of the spinal muscular atrophy patients show a homozygous absence of exons 7 and 8, or exon 7 only, in SMN1, the telomeric copy of the SMN gene. We report a young male patient with neurogenic symptoms and sparse muscle fiber atrophy, suggestive of a mild form of type III spinal muscular atrophy. He was found to be a carrier of intragenic mutations in both copies of the SMN gene, exhibiting a homozygous duplication of exons 7 and 8 in SMN1 and a homozygous deletion of exon 8 as well as a heterozygous deletion of exon 7 in SMN2. However, an intact full-length SMN1 complementary deoxyribonucleic acid was identified, and SMN protein levels in a muscle specimen were identical to that of a healthy control, formally excluding the diagnosis of spinal muscular atrophy III.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-12-11 | Journal of Child Neurology |