Spastic Ataxia 2

Clinical Characteristics

Ocular Features:

Horizontal nystagmus is present in some patients.

Systemic Features:

Cerebellar ataxia, dysarthria, and spasticity of the lower limbs appear in the first two decades of life. The spasticity may involve all 4 limbs late in life. Cognition is not impacted. Cervical dystonia has been noted. No consistent changes have been found on brain imaging. The neurologic signs are slowly progressive although patients may remain ambulatory.

Tremor, clonus, and extrapyramidal chorea has been seen in several families with what has been called spastic paraplegia-58 which may be the same disorder as SPAX2 since mutations are found in the same gene (KIF1C). Symptoms and prognosis are similar in these conditions except for the reported presence of developmental delay and mild mental retardation in some individuals diagnosed to have SPG58.

Genetics

This is an autosomal recessive condition as the result of homozygous mutations in the KIF1C gene (17p13.2).

Treatment

Treatment Options:

No effective treatment for this disease is available although speech and physical therapy may be helpful.

References

Article Title:

Motor protein mutations cause a new form of hereditary spastic paraplegia [1]

Caballero Oteyza A, Battaloglu E, Ocek L, Lindig T, Reichbauer J, Rebelo AP, Gonzalez MA, Zorlu Y, Ozes B, Timmann D, Bender B, Woehlke G, Zuchner S, Schols L, Schule R. Motor protein mutations cause a new form of hereditary spastic paraplegia. Neurology. 2014 May 7. [Epub ahead of print].

PubMed ID:

24808017

KIF1C mutations in two families with hereditary spastic paraparesis and cerebellar dysfunction [2]

Dor T, Cinnamon Y, Raymond L, Shaag A, Bouslam N, Bouhouche A, Gaussen M, Meyer V, Durr A, Brice A, Benomar A, Stevanin G, Schuelke M, Edvardson S. KIF1C mutations in two families with hereditary spastic paraparesis and cerebellar dysfunction. J Med Genet. 2014 Feb;51(2):137-42.

PubMed ID:

24319291

Exome sequencing links corticospinal motor neuron disease to common neurodegenerative disorders [3]

Novarino G, Fenstermaker AG, Zaki MS, Hofree M, Silhavy JL, Heiberg AD, Abdellateef M, Rosti B, Scott E, Mansour L, Masri A, Kayserili H, Al-Aama JY, Abdel-Salam GM, Karminejad A, Kara M, Kara B, Bozorgmehri B, Ben-Omran T, Mojahedi F, Mahmoud IG, Bouslam N, Bouhouche A, Benomar A, Hanein S, Raymond L,Forlani S, Mascaro M, Selim L, Shehata N, Al-Allawi N, Bindu PS, Azam M, Gunel M, Caglayan A, Bilguvar K, Tolun A, Issa MY, Schroth J, Spencer EG, Rosti RO, Akizu N, Vaux KK, Johansen A, Koh AA, Megahed H, Durr A, Brice A, Stevanin G, Gabriel SB, Ideker T, Gleeson JG. Exome sequencing links corticospinal motor neuron disease to common neurodegenerative disorders. Science. 2014 Jan 31;343(6170):506-11.

PubMed ID:

24482476