Affected genes: LIX1 and LNPEP
Transmission: Autosomal recessive
Mutation: Felis_catus_9.0 A1 g.161036890_161176706del
~140 kb deletion removing exons 4-6 of LIX1 and all except exon 1 of LNPEP
Lien OMIA: 002389-9685
Breeds suitable for testing: Maine Coon, Highland LynxSymptoms:
Affected animals are deficient in LNPEP and LIX1. LNPEP is an enzyme found in the endoplasmic reticulum that utilize peptides for antigen presentation. The function of LIX1 is unknown, but mainly expressed in spinal cord neurons. It is probably necessary for the development and maintenance of neurons
Affected cats begin to show signs between 13 and 17 weeks. Signs include gait abnormalities and muscle tremor primarily involving the hindquarters. Limb weakness is progressive over several months. By five months of age, muscle atrophy is evident in all limbs, and affected cats exhibit a characteristic gait with splayed forelimbs and a rocking pelvis. Disease progression slows around 4 to 8 months and affected cats with clinical signs of varying severity have lived for at least 8 years (He et al., 2005).
References:
Fyfe, J.C., Menotti-Raymond, M., David, V.A., Brichta, L., Schäffer, A.A., Agarwala, R., Murphy, W.J., Wedemeyer, W.J., Gregory, B.L., Buzzell, B.G., Drummond, M.C., Wirth, B., O'Brien, S.J. : An approximately 140-kb deletion associated with feline spinal muscular atrophy implies an essential LIX1 function for motor neuron survival. Genome Res 16:1084-90, 2006. Pubmed reference: 16899656. DOI: 10.1101/gr.5268806
He, Q., Lowrie, C., Shelton, GD., Castellani, RJ., Menotti-Raymond, M., Murphy, W., O'Brien, SJ., Swanson, WF., Fyfe, JC. 2005 Inherited motor neuron disease in domestic cats: a model of spinal muscular atrophy. Pediatr Res 57:324-30, 2005. Pubmed reference: 15635053. DOI: 10.1203/01.PDR.0000153625.46892.6F