SUMMARY AND CONCLUSIONS A new approach in measuring the incidence of traits which appear at widely variable ages in a population is reported. The new approach is agerelated and yields a cumulative incidence rate and an associated standard error at each age interval considered. This method was applied to a defined population of Beagle dogs in which the occurrence of clinically observed spontaneous convulsive seizures have been systematically reported and recorded. The cumulative rate of dogs affected by seizures and an associated standard error have been reported for the entire population. The cumulative rates of affected offspring of 2 sires (FD53 and FD106) have been compared with the rate of affected offspring of the other sires used in the colony; these rates were 10.1 and 15.3% (for sires FD53 and FD106) and 5.7% (for the other sires). These seizure rates, along with other supporting pedigree data, led to a conclusion that the occurrence of convulsive seizures has a genetic basis in the Beagle colony. The highest cumulative rates of affected dogs and the associated standard error have been reported for each sex separately. Differences in the maximum rates observed for the sexes (males 11.9%, females 2.6%) led to the conclusion that the two sexes behave differently with respect to the rate of occurrence of seizures. Two possible genetic hypotheses (a simple sex-linked recessive and a simple autosomal recessive) were examined, neither of which give a completely satisfactory explanation of the observed data. A genetic hypothesis, utilizing two loci (one an autosomal recessive, the other a sex-linked suppressor), was advanced. A wide range in the age of the initial observed seizure is reported, with an apparent minimal age of approximately 1 year.
No takes yet. Share an insight, caveat, or question.
Bielfelt et al. (1971) studied this question.