The first symptom is often cramps in the hands and / or feet 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 foot and / or 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.

The condition is slowly progressive and with time will start to impact muscles in the legs and arms. People with this condition have a normal life expectancy.

DSMA-V is a form of genetic peripheral neuropathy that affects the motor neurons, so is also often referred to as distal hereditary motor neuropathy, type 5. Symptoms and effects of genetic peripheral neuropathy are described in more detail in the information published by the charity Charcot-Marie-Tooth UK (see below under Support and Resources).

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.

Charcot-Marie Tooth UK:

enquiries@cmt.org.uk Phone: 0300 323 6316

See CMT and You  and CMT Symptoms

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)