OMIA 001757-9796 : Epilepsy, juvenile idiopathic in Equus caballus

Possibly relevant human trait(s) and/or gene(s)s (MIM numbers): 121200 (trait) , 121201 (trait)

Mendelian trait/disorder: unknown

Considered a defect: yes

Markers: Polani et al. (2018): "Initial whole genome comparisons between a small cohort of nine diagnosed foals (cases [diagnosed primarily on clinical grounds]) and 27 controls from other horse breeds identified variants uniquely shared amongst the case cohort. Further validation via targeted resequencing of these variants, that pertain to non-intergenic regions, on additional eleven case individuals revealed a single 19bp deletion coupled with a triple-C insertion (Δ19InsCCC) within the TRIM39-RPP21 gene readthrough that was uniquely shared across all case individuals, and absent from three additional Arabian controls." Given the limitations of these data, Polani et al. (2018) concluded that "Further evaluation of the sensitivity and specificity of the Δ19InsCCC allele within additional cohorts of the Arabian horse is warranted in order to validate its credibility as a marker for JIE".

Rivas et al. (2019) provided further evaluation by genotyping (via sequencing) the Δ19InsCCC variant in "nine EEG-phenotyped affected and nine unaffected Egyptian Arabian horses". The results showed that "There was no significant genotypic (P = 1.00) or allelic (P = 0.31) association with the ∆19InsCCC variant and JIE status [as definitively determined by EEG]." Rivas et al. (2019) concluded that "The previously reported markers in TRIM39-RPPB1 are therefore not associated with JIE in well-phenotyped samples."


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.
2019 Rivas, V.N., Aleman, M., Peterson, J.A., Dahlgren, A.R., Hales, E.N., Finno, C.J. :
<i>TRIM39-RPP21</i> Variants (∆19InsCCC) Are Not Associated with Juvenile Idiopathic Epilepsy in Egyptian Arabian Horses. Genes (Basel) 10:, 2019. Pubmed reference: 31623255. DOI: 10.3390/genes10100816.
2018 Polani, S., Dean, M., Lichter-Peled, A., Hendrickson, S., Tsang, S., Fang, X., Feng, Y., Qiao, W., Avni, G., Kahila Bar-Gal, G. :
Sequence variant in the TRIM39-RPP21 gene readthrough is shared across a cohort of Arabian foals diagnosed with juvenile idiopathic epilepsy. Journal of Genetic Mutation Disorders 1:103:, 2018.
2015 Lacombe, V.A. :
Seizures in horses: diagnosis and classification. Vet Med (Auckl) 6:301-308, 2015. Pubmed reference: 30101115. DOI: 10.2147/VMRR.S62078.
2012 Lichter-Peled, A., Polani, S., Stanyon, R., Rocchi, M., Kahila Bar-Gal, G. :
Role of KCNQ2 and KCNQ3 genes in juvenile idiopathic epilepsy in Arabian foals. Vet J :, 2012. Pubmed reference: 23182620. DOI: 10.1016/j.tvjl.2012.08.024.
van der Ree, M., Wijnberg, I. :
A review on epilepsy in the horse and the potential of Ambulatory EEG as a diagnostic tool. Vet Q :, 2012. Pubmed reference: 23163553. DOI: 10.1080/01652176.2012.744496.
2011 Lacombe, V.A., Mayes, M., Mosseri, S., Reed, S.M., Fenner, W.R., Ou, H.T. :
Epilepsy in horses: Aetiological classification and predictive factors. Equine Vet J :, 2011. Pubmed reference: 22168451. DOI: 10.1111/j.2042-3306.2011.00527.x.
2006 Aleman, M., Gray, L.C., Williams, D.C., Holliday, T.A., Madigan, J.E., LeCouteur, R.A., Magdesian, K.G. :
Juvenile idiopathic epilepsy in Egyptian Arabian foals: 22 cases (1985-2005). J Vet Intern Med 20:1443-9, 2006. Pubmed reference: 17186863.

Edit History

  • Created by Frank Nicholas on 30 Nov 2012
  • Changed by Frank Nicholas on 22 Oct 2019