An analysis of disease severity based on SMN2
copy number in adults with spinal muscular atrophy.
In all affected and carrier samples, SMN1 and SMN2
gene copy numbers were independently determined using a previously published quantitative PCR (21).
With respect to SMA diagnostics, we evaluate the method using the critical C-to-T substitution at position +6 of exon 7 (c.840C>T) in SMA for differentiation between SMN1 and SMN2
. The copy numbers and relative ratio of the SMN1 and SMN2
genes obtained with this platform can be determined to diagnose the status of SMA carriers in the general population.
Approximately 95% of patients with SMA had homozygous deletion of SMN1 and around 5% of patients carried compound heterozygous mutation with one allele deleted and a subtle variation in the other allele. Molecular detection of SMN1 variations is effective and specific for diagnosis of SMA; however, it is more challenging than other monogenic disorders because of the existence of the nearly identical SMN2
, with only five nucleotides differentiating from SMN1 .
genes also produce SMN protein but in different forms, and only a small percentage of this production is functional.
 Human genes: STRC, stereocilin; PMS2, PMS1 homolog 2, mismatch repair system component; PKD1, polycystin 1, transient receptor potential channel interacting; SMN1, survival of motor neuron 1, telomeric; CATSPER2, cation channel sperm associated 2; SMN1, survival of motor neuron 1, telomeric; SMN2
, survival of motor neuron 2, centromeric.
Significant difference among the DCP, SCP, and HC groups was found within four RSNs (P <0.05, corrected by FDR), including the cerebellum network, SMN2
, LFPN, and SN (Table 2).
Report demonstrated that drug compound altered specific splicing patterns of gene (survival motor neuron gene, SMN2
gene lacks exon 7) which represented a new approach to modification of gene expression in disease treatment .
The company said ISIS-SMNRx is designed to alter the splicing of a closely related gene (SMN2
) to increase production of fully functional SMN protein.
However, all of human patients have SMN2
gene, a duplicate of SMN1 gene, in which there are 5-point mutations compared with SMN1 gene [13, 22].
Chicago, IL, August 10, 2013 --(PR.com)-- This program will systematically assess the effect of backbone chemistry on the therapeutic efficacy of Antisense Oligonucleotides (ASO) that target the ISS-N1 region of the SMN2