[Mutation analysis of SMN gene in a patient and his family with spinal muscular atrophy].
OBJECTIVE
To perform mutation analysis and describe the genotype of the SMN gene in a patient with spinal muscular atrophy (SMA) and his family.


METHODS
Deletion analysis of the SMN1 exon 7 by conventional PCR-restriction fragment length polymorphism (RFLP) and allele-specific PCR, and gene dosage of SMN1 and SMN2 by multiplex ligation-dependent probe amplification (MLPA) were performed for the patient and his parents; reverse transcriptase (RT)-PCR and sequencing were performed for the patient. To determine whether the SMN variant was exclusive to transcripts derived from SMN1, the RT-PCR product of the patient was subcloned and multiple clones were sequenced directly; PCR of SMN exon 5 from the genomic DNA of the parents and direct sequencing were performed to confirm the mutation.


RESULTS
In SMN1 exon 7 deletion analysis, no homozygous deletion of the SMN1 was observed in the family; the gene dosage analysis by MLPA showed that the patient had 1 copy of SMN1 and 1 copy of SMN2 his father had 2 copies of SMN1 and 2 copies of SMN2, and his mother had 1 copy of SMN1 and no SMN2. A previously unreported missense mutation of S230L was identified from the patient and this mutation was also found in his father.


CONCLUSIONS
A novel missense mutation of S230L was identified in the SMA family and the genotype of the family members were investigated.
Zeng
Jian
J
Fuzhou General Hospital, Nanjing Military Region, Fuzhou, Fujian, 350025 People's Republic of China.
Lin
Yan-hong
YH
Yan
Ai-zhen
AZ
Cai
Mei-ying
MY
Ke
Long-feng
LF
Lan
Feng-hua
FH
D001483:Base Sequence; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009134:Muscular Atrophy, Spinal / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055532:SMN Complex Proteins / Q000235:genetics*; D014897:Spinal Muscular Atrophies of Childhood / Q000235:genetics; D055533:Survival of Motor Neuron 1 Protein / Q000235:genetics*; D055517:snRNP Core Proteins / Q000235:genetics
D055532:SMN Complex Proteins; D055533:Survival of Motor Neuron 1 Protein; D055517:snRNP Core Proteins