[Detection of SMN gene deletions in spinal muscular atrophy].
OBJECTIVE
Survival motor neuron gene(SMN) and neuronal apoptosis inhibitory protein gene (NAIP) have been identified as the candidates of progressive spinal muscular atrophy (SMA)-determining genes. The aims of this study were to investigate the absence of SMN gene exon 7 in Chinese SMA patients, to confirm the relationship between the deletion of the SMN and SMA further, and to establish methods for gene diagnosis and prenatal diagnosis of SMA.


METHODS
PCR-SSCP with silver staining method was used to detect the genomic DNA of 37 SMA patients and 30 normal individuals for deletions of SMN exon 7.


RESULTS
Homozygous deletion of the SMN exon 7 was identified in 86.7%(13/15) of type I SMA patients and 86.4%(19/22) of type II patients. In the 88 controls (including parents of patients and normal individuals), homozygous absence of SMA exon 7 was only found in a mother of a patient.


CONCLUSIONS
The data support that homozygous absence of SMN exon 7 is strongly associated with SMA. The percentage of homozygous deletions in this study is almost as high as that reported by other researchers. This method is useful, reliable and effective for gene diagnosis and prenatal diagnosis of SMA.
Yang
T
T
Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medecal College, Beijing 100005 P. R. China.
Yuan
L
L
Liu
T
T
Zhou
W
W
Wu
H
H
Zhao
S
S
Shun
L
L
Huo
L
L
Ma
S
S
Lin
Z
Z
D017362:Cyclic AMP Response Element-Binding Protein; D017353:Gene Deletion; D005820:Genetic Testing; D006801:Humans; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D051616:Neuronal Apoptosis-Inhibitory Protein; D011296:Prenatal Diagnosis; D016601:RNA-Binding Proteins; D055532:SMN Complex Proteins
D017362:Cyclic AMP Response Element-Binding Protein; C496800:NAIP protein, human; D009419:Nerve Tissue Proteins; D051616:Neuronal Apoptosis-Inhibitory Protein; D016601:RNA-Binding Proteins; D055532:SMN Complex Proteins