Rapid diagnosis of spinal muscular atrophy using tetra-primer ARMS PCR assay: simultaneous detection of SMN1 and SMN2 deletion.
Spinal muscular atrophy (SMA), the leading genetic cause of death in childhood, is an autosomal recessive neuromuscular disorder characterized by progressive muscle weakness, associated with deletions of the survival motor neuron 1 (SMN1) gene. Approximately 94% of SMA patients carry homologous deletions of SMN1 exon(s) 7 (and 8). Because of the high incidence and severity of the disease, precise detection and quantification of SMN1 and SMN2 gene copy numbers is essential for diagnosis and genetic counseling. We have developed a reliable single-tube tetra-primer PCR assay to simultaneously detect both the SMN1 and SMN2 exon 7 deletion using the advantage of C/T difference at nucleotide position of 840 in exon 7. The assay has been optimized and tested in 48 healthy controls, 20 known patients with SMA, 12 carriers (one SMN1 copy), and 8 amniotic fluids suspected of having SMA for whom we had determined the SMN1/SMN2 deletion by an additional PCR-RFLP method. We have observed complete concordance between methods. Our tetra-primer PCR assay is sensitive, low-cost, and easy to use method for simultaneous detection of both SMN1 and SMN2 deletion, which could be used even in "low-tech" laboratories.
Baris
Ibrahim
I
Department of Chemical and Biological Engineering, KOC University, Istanbul, Turkey. ibaris@ku.edu.tr
Etlik
Ozdal
O
Koksal
Vedat
V
Arican-Baris
S Tugba
ST
D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers / Q000235:genetics*; D004587:Electrophoresis, Agar Gel; D005192:Family Health; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis / Q000235:genetics; D017353:Gene Deletion; D006801:Humans; D008297:Male; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis* / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012680:Sensitivity and Specificity; D055533:Survival of Motor Neuron 1 Protein / Q000235:genetics*; D055540:Survival of Motor Neuron 2 Protein / Q000235:genetics
D017931:DNA Primers; C526471:SMN1 protein, human; C526477:SMN2 protein, human; D055533:Survival of Motor Neuron 1 Protein; D055540:Survival of Motor Neuron 2 Protein; D004247:DNA