Spinal Muscular Atrophy Genetics
Published : 2009-04-07 - Updated : 2020-03-25
Author : BioMed Central - Contact: biomedcentral.com
Synopsis* : BMC Medicine details the first research focused on human muscle tissue atrophied due to a genetic condition. SMA type I is also known as severe infantile SMA or Werdnig-Hoffmann disease. Manifesting rapidly in infants, babies diagnosed with type I SMA do not generally live past a year of age. SMA type III represents a milder form of the disorder. It has a later onset and affected patients may be able to walk but later lose this ability.
Caused by a mutation of the SMN gene, spinal muscular atrophy (SMA) is an infantile and juvenile neurodegenerative disorder where motor neuron loss causes progressive paralysis. A new study published in the open access journal BMC Medicine details the first research focused on human muscle tissue atrophied due to a genetic condition, and sheds light on two distinct mechanisms at work in different forms of SMA.
A research team from Italy, led by Gerolamo Lanfranchi, analyzed muscle biopsies and genomic DNA from peripheral blood of four SMA I and five SMA III patients from the Neuromuscular Bank organized by Corrado Angelini at the University of Padova, to investigate which other muscle genes, other than the SMN defect, played a role in atrophy.
They used microarray and quantitative real-time PCR to study at transcriptional level the effects of a defective SMN gene in skeletal muscles affected by the two forms of SMA: the most severe, type I (infantile), and the milder type III (juvenile).
SMA type I is also known as severe infantile SMA or Werdnig-Hoffmann disease.
Manifesting rapidly in infants, babies diagnosed with type I SMA do not generally live past one year of age.
SMA type III represents a milder form of the disorder. It has a later onset and affected patients may be able to walk but later lose this ability.
The two forms of SMA gave distinct expression signatures.
The SMA III muscle transcriptome is close to normal, whereas in SMA I gene expression is significantly altered.
Genes implicated in signal transduction were up-regulated in SMA III whereas those involved in energy metabolism and muscle contraction were consistently down-regulated in SMA I.
"Our work indicates that SMA I and III muscles are in different phases: the 'prolonged' atrophic condition typical of the SMA I muscle and the coexistence of atrophy and hypertrophy in SMA III muscle," says Lanfranchi.
Previous studies have investigated transcriptional changes in mouse or rat muscle atrophied due to physiopathological conditions, but this is the first to use human tissue affected by a genetic atrophic condition.
"Different atrophy-hypertrophy transcription pathways in muscles affected by severe and mild spinal muscular atrophy," Caterina Millino, Marina Fanin, Andrea Vettori, Paolo Laveder, Maria Luisa Mostacciuolo, Corrado Angelini and Gerolamo Lanfranchi BMC Medicine.
Spinal Muscular Atrophy Genetics | BioMed Central (biomedcentral.com). Disabled World makes no warranties or representations in connection therewith. Content may have been edited for style, clarity or length.
You're reading Disabled World. Be sure to check out our homepage for further informative disability news, reviews, disability sports events, exclusive stories and how-tos. You can also find us on Twitter, Facebook, and LinkedIn.
Related Mobility Impairments Documents
- 1 - Dystonia: Types, Causes and General Overview : Dystonia is a neurological movement disorder characterized by involuntary muscle contractions, which force certain parts of the body into abnormal, sometimes painful, movements or postures..
- 2 - Foot Drop: Symptoms - Causes - Treatments : Information regarding foot drop, a sign of an underlying muscular, neurological, or anatomical issue.
- 3 - Dopa-Responsive Dystonia: Symptoms, Causes, Treatments : Information regarding Dopamine-responsive dystonia (DRD), a genetic movement disorder which usually manifests during early childhood.
- 4 - Family Members, Friends, and Caring for People with Mobility Disabilities : Ways people can help family members who have a permanent or temporary disability involving mobility impairment.
- 5 - Prenatal Heart Defects in Spinal Muscular Atrophy Cases : Spinal muscular atrophy is caused by loss of a gene known as SMN1.
*Disclaimer: Disabled World provides general information only. Materials presented are in no way meant to be a substitute for professional medical care by a qualified practitioner, nor should they be construed as such. Any 3rd party offering or advertising on disabled-world.com does not constitute endorsement by Disabled World. View our Advertising Policy for further information. Please report outdated or inaccurate information to us.
Journal: Disabled World. Language: English (U.S.). Author: BioMed Central. Electronic Publication Date: 2009-04-07 - Revised: 2020-03-25. Title: Spinal Muscular Atrophy Genetics, Source: <a href=https://www.disabled-world.com/disability/types/mobility/sma-genetics.php>Spinal Muscular Atrophy Genetics</a>. Retrieved 2021-05-05, from https://www.disabled-world.com/disability/types/mobility/sma-genetics.php - Reference: DW#264-1389.