Copy number analysis of survival motor neuron genes by multiplex ligation-dependent probe amplification.
OBJECTIVE
To determine the copy number of survival motor genes using multiplex ligation-dependent probe amplification.


METHODS
Three hundred seventy-three subjects were recruited and divided into three groups. Group 1 included 310 subjects without a history of muscular atrophy, Group 2 consisted of 18 patients and 45 carriers of spinal muscular atrophy, and Group 3 included 20 subjects who were previously tested with denatured high-performance liquid chromatography. The copy number of survival motor neuron 1 and survival motor neuron 2 genes was determined with a commercially available multiplex ligation-dependent probe amplification kit.


RESULTS
Twenty-one genotypes of the survival motor neuron genes could be clearly defined in this series. The whole process of genotyping took <48 hours. In Group 1, 2:2 (survival motor neuron 1:survival motor neuron 2) was most common (52.90%), followed by 2:1 (30.32%); six (1.94%) subjects were found to be carriers of 1:2 or 1:3. In Group 2, all 18 patients had zero copies of the survival motor neuron 1 gene and variable copies of the survival motor neuron 2 gene. In Group 3, three subjects who had been told they were carriers of spinal muscular atrophy turned out to be noncarriers by multiplex ligation-dependent probe amplification. All 51 carriers from Groups 1 and 2 had one copy of the survival motor neuron 1 gene and one to four copies of the survival motor neuron 2 gene.


CONCLUSIONS
Multiplex ligation-dependent probe amplification is a simple and efficient method for copy number analysis of survival motor neuron genes. It can be used to detect the homozygous and heterozygous survival motor neuron deletion of spinal muscular atrophy.
Huang
Chien-Hao
CH
Genephile Bioscience Laboratory, Ko's Obstetrics and Gynecology, Taipei, Taiwan.
Chang
Yih-Yuan
YY
Chen
Chung-Hsiung
CH
Kuo
Yen-Shi
YS
Hwu
Wuh-Liang
WL
Gerdes
Tommy
T
Ko
Tsang-Ming
TM
D017362:Cyclic AMP Response Element-Binding Protein / Q000235:genetics*; D015342:DNA Probes; D018628:Gene Dosage; D020022:Genetic Predisposition to Disease; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis* / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D016601:RNA-Binding Proteins / Q000235:genetics*; D055532:SMN Complex Proteins; D013624:Taiwan
D017362:Cyclic AMP Response Element-Binding Protein; D015342:DNA Probes; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; D055532:SMN Complex Proteins