SMA is caused by recessive mutations in the survival motor neuron 1 (SMN1) gene.
About 95% of SMA cases are caused by homozygous deletions of exon 7 in SMN1, whereas the remaining cases exhibit a heterozygous mutation on one allele and other deleterious variants on the other.
The human genome harbors a paralogous gene, SMN2, that differs from SMN1 by only a few nucleotides including a C to T transition in exon 7. This base change causes the skipping of exon 7 in most SMN2 transcripts.
Approximately 90% of transcript isoforms encode a truncated unstable protein; full-length, functional SMN protein results from approximately 10% of SMN2 transcripts.
INOGene-SMA PCR Detection Kit
Nucleic acid extraction can be performed from whole blood samples with any commercial DNA isolation/extraction kits.
The Kit provides detection of the single nucleotide mutation occurs in the 840th base which causes skipping exon 7 and thus, spinal muscular atrophy.
This single nucleotide change in the exon 7 is detected by using specially designed oligonucleotides and MGB tagged probes.
The curves and Ct values of FAM, HEX, and CY5 fluorophores are analyzed at the end of real-time PCR to determine homozygous and heterozygous mutations in the individual.
The kit comes in packages of 25 and 50 reactions and includes reaction mix, primer probe mix, negative template control, and positive controls.
INOGene-SMA PCR Detection Kit
Spinal Muscular Atrophy (SMA) is a neurodegenerative, monogenic, and autosomal recessive disease that occurs by decreasing SMN protein levels in motor neurons depending on a single nucleotide mutation in the SMN1 gene.
SMA can be seen by the ratio of 1/10000 and depending on its type it can result in death, life-long disability, and muscular atrophy because of the death of motor neurons in the body. Classificication of SMA is shown in the table below.
| Type | Age of Onset | Maximal Motor Milestone |
Motor Ability and Additional Features |
Prognosis |
| SMA 0 | Before Birth | None | Unable to sit or roll | Death within weeks |
| SMA I | 2 weeks or 3 months | None | Unable to sit or roll | Death by to 2 years |
| SMA II | 6 to 18 months | Sitting | Unable to walk independently | Survival into adulthood |
| SMA III | <3 years, <12 years | Walking | May lose ability to walk | Normal life span |
| SMA IV | >30 years or 10 to 30 | Normal | Mild motor impairment | Normal life span |
