The first symptom is often cramps in the hand brought on by exposure to cold temperatures. Symptoms usually begin during adolescence, but onset varies from infancy to the mid-thirties.

Over time this first symptom is followed by weakness and wasting (atrophy) of hand muscles, specifically on the thumb-side of the index finger and in the palm at the base of the thumb. It is also common to have a high foot arch, and some people develop difficulties with walking.

People with this condition have a normal life expectancy.

DSMA-V has been linked to mutations in several different genes:

• For further information about the BSCL2  gene ^1-2  > 
• For further information about the GARS1 gene^3-4 >
• For further information about the REEP1 gene ^{5-6 >}

Based on the gene that causes the condition, DSMA-V is sometimes subdivided into DSMA-VA (GARS1), DSMA-VB (REEP1) and DSMA-VC (BSCL2).

DSMA-V has an autosomal dominant inheritance pattern, which means that only one faulty gene copy passed on from a parent with the condition will cause the condition.

Though not a substitute for professional medical advice, the US National Library of Medicine, Genetics Home Reference provides more information. Click here to read more.

SMA UK

• Phone: 01789 267520
• Email: office@smauk.org.uk
• Website: www.smauk.org.uk

Provides information and support for anyone in the UK affected by any form of SMA.

Contact

• Phone: 0808 808 3555
• Website: www.contact.org.uk

Provides information and support for families with children with a disability.

1. Windpassinger et al. (2004) Heterozygous missense mutations in BSCL2 are associated with distal hereditary motor neuropathy and Silver syndrome. Nat Genetics 36: 271-276.
2. https://www.omim.org/entry/619112 (last accessed 21st August 2024)
3. Antonellis et al. (2003) Glycyl tRNA synthetase mutations in Charcot-Marie-Tooth disease type 2D and distal spinal muscular atrophy type V. Am J Hum Genet 72: 1293-1299.
4. https://www.omim.org/entry/600794 (last accessed 21st August 2024)
5. Beetz et al. (2012) Exome sequencing identifies a REEP1 mutation involved in distal hereditary motor neuropathy type V. Am J Hum Genet 91: 139-145.
6. https://www.omim.org/entry/614751 (last accessed 21st August 2024)