Spinal Muscular atrophy (SMA) is a group of diseases that result in progressive muscle deterioration and neuromuscular failure. As it is an inherited autosomal recessive disease meaning the sufferer must have both defective survival motor neuron (SMN1) genes, from each parent, to have the symptoms. There are five subtypes of SMA, categorised by the age at which the symptoms begin to appear, with type I, II and III occurring in childhood are more severe than type IV, which appears in later adulthood and X-linked SMA (http://www.genome.gov/20519681).
Type I begins to affect infants from birth to six month old and is the most severe, as it affects their food intake and repertory system. Type affects children between 6 and 18 months old. Type …show more content…
The absence of this gene in patients with SMA causes these motor neurones to perish and leave them with loss of function and incapability (http://ghr.nlm.nih.gov/condition/spinal-muscular-atrophy). Since motor neurones connect the spinal cord to your effector muscles, when SMN1 isn’t present the motor neurones waste away and the muscle is no longer able to contract. In 95% of SMA cases the mutated gene line is caused by a deletion of bases and the other 5% have point mutations, which in turn creates a frame shift of base sequences which changes the final amino acid sequence/primary structure of the protein. This in turn affects the whole protein structure rendering it useless (http://www.smasupportuk.org.uk/the-genetics-of-sma).
When there is no SMN1 made in the cell the SMN2 gene is the backup, but unfortunately the proteins formed by SMN2 are not sufficient enough to work alone. Therefore those with more SMN2 have less severe SMA than those with less showing the usefulness of having these extra copies (http://www.genome.gov/20519681). The reason why SMA is so hard treat is due to the fact that it isn't possible to inject this protein into the muscles/ingest it as it is fashioned within individual cells for use in those particular cells only (Wirth, …show more content…
There are however many ethical issues revolving around this topic, such as who determines which genes are ‘good’ or ‘bad’? Will gene therapy make certain traits and characteristics undesirable and thus making us more un-accepting? If we can use gene therapy to change our genes, can we use it to change our phenotype or intellectual abilities? (http://ghr.nlm.nih.gov/handbook/therapy/ethics) These are the types of questions many raise when talking about gene therapy and why it shouldn’t be used widespread. Medications which are also being trialled are those such as riluzole which aim to cure SMA
Type I begins to affect infants from birth to six month old and is the most severe, as it affects their food intake and repertory system. Type affects children between 6 and 18 months old. Type …show more content…
The absence of this gene in patients with SMA causes these motor neurones to perish and leave them with loss of function and incapability (http://ghr.nlm.nih.gov/condition/spinal-muscular-atrophy). Since motor neurones connect the spinal cord to your effector muscles, when SMN1 isn’t present the motor neurones waste away and the muscle is no longer able to contract. In 95% of SMA cases the mutated gene line is caused by a deletion of bases and the other 5% have point mutations, which in turn creates a frame shift of base sequences which changes the final amino acid sequence/primary structure of the protein. This in turn affects the whole protein structure rendering it useless (http://www.smasupportuk.org.uk/the-genetics-of-sma).
When there is no SMN1 made in the cell the SMN2 gene is the backup, but unfortunately the proteins formed by SMN2 are not sufficient enough to work alone. Therefore those with more SMN2 have less severe SMA than those with less showing the usefulness of having these extra copies (http://www.genome.gov/20519681). The reason why SMA is so hard treat is due to the fact that it isn't possible to inject this protein into the muscles/ingest it as it is fashioned within individual cells for use in those particular cells only (Wirth, …show more content…
There are however many ethical issues revolving around this topic, such as who determines which genes are ‘good’ or ‘bad’? Will gene therapy make certain traits and characteristics undesirable and thus making us more un-accepting? If we can use gene therapy to change our genes, can we use it to change our phenotype or intellectual abilities? (http://ghr.nlm.nih.gov/handbook/therapy/ethics) These are the types of questions many raise when talking about gene therapy and why it shouldn’t be used widespread. Medications which are also being trialled are those such as riluzole which aim to cure SMA