Canine epilepsy: a genetic counselling programme for keeshonds

Abstract

The predisposition of keeshonds (Dutch barge dogs) to an idiopathic epilepsy appears to be determined by a single autosomal recessive gene. The pedigrees of 15 litters which included animals diagnosed as epileptic ('fitters') were compared with those of 34 contemporary, normal animals. The pedigrees of all the fitters traced back, on both the paternal and maternal sides, to a common ancestor. Subsequently, further pedigrees and details of litters were gathered. If both parents of a fitter were heterozygous ('carriers'), the progeny (120 in number) of all known carrier x carrier matings would be expected to have a ratio of three phenotypically normal animals to one fitter, that is, 90:30. The ratio observed (91:29) was not significantly different. The Keeshond Club has published a list from which the identities of carriers can be inferred, with the intention that known carriers should be excluded from breeding. A genetic counselling programme has been in operation since 1989, which is based on advising breeders on the probability that the offspring of proposed matings would be fitters or carriers; advice has been given on 77 proposed matings. The mean probability that the proposed matings would result in carriers has declined significantly, and this is consistent with a decline in the frequency of the gene for this form of epilepsy in the breed.

Clinical characteristics and mode of inheritance of familial focal seizures in Standard Poodles

“…In most studies [6][7][8][9][10]17,18 of the mode of inheritance of IE in specific dog breeds, pedigree data were consistent with some form of autosomal recessive inheritance. This strongly suggests that a dog' s sire and dam both contribute to the dog' s inherited susceptibility to IE.…”

Segregation analysis of epilepsy in the Belgian tervueren dog

“…A recent investigation in the Belgian tervueren (Famula and others 1997) estimated a heritabilify of 077 for the disorder. Earlier work by Hall and Wallace (1996) found evidence of a single recessive gene contributing a predisposition to epilepsy Veterinary Record (2000) in keeshonds. 147,[218][219][220][221] Little is known of the genetics of epilepsy in dogs, but much has been uncovered in human beings (Toth and oth-T. R. Famula, PhD, ers 1995, Zara andothers 1995).…”

Inhibitory and excitatory neurotransmitters in the cerebrospinal fluid of epileptic dogs

“…3-5 Although inheritance appears to play an important role in the transmission of epilepsy in dogs, the precise pathophysiologic characteristics of the disorder are poorly understood. 1,[6][7][8][9][10][11][12][13] Proposed pathophysiologic mechanisms in human epilepsy include changes in neurotransmitter function, neurotransmitter concentration, 14 alterations in the expression of receptor or transmitter transporters, 15,16 and changes in function of ion channels or enzymes involved in neurotransmitter metabolism. 17 Although results a study 18 of neurochemical changes in epilepsy indicate that a decrease in the concentrations of γ γ-aminobutyric acid (GABA) in the CSF may lead to seizures, and an increase in CSF concentrations of GABA may have anticonvulsant effects, the exact role of GABA during epileptic activity remains controversial.…”