Abstracts

Southwest Foundation for Biomedical Research (SFBR) in San Antonio, TX, manages the world[apos]s largest baboon colony, currently comprising about 3800 baboons. More than 1500 baboons[mdash]primarily [italic]P.h.anubis[/italic] (64%), [italic]P.h.cynocephalus[/italic] (4%), and their hybrids (29%)[mdash]are members of a single pedigree that is used for genetic analysis. The baboon is ideal for development as a genetic model of human disorders because baboon and human share many genetic, anatomical, biochemical, and physiological features, and we are using the colony at SFBR to develop the baboon as a nonhuman primate animal model for the genetics of idiopathic generalized epilepsy in humans. It has long been known that baboons at SFBR suffer spontaneous seizures. The prevalence of seizures in the baboon colony is 20[ndash]30%, and about 10[ndash]20 new cases per year are reported, corresponding to an incidence of about 2%. We are undertaking a retrospective case-detection survey of veterinary records to evaluate living and dead members of the colony for a history of seizures, and to better characterize the epidemiology of seizures in the colony. We have reviewed records for 761 baboons (235 living, 526 dead, 802 F, 871 M) and identified as seizures 1353 events in 444 baboons. Of these, 579 (43%) seizures were witnessed, and 774 (57%) were suspected on the basis of periorbital or other facial trauma, which has been found to be a reliable proxy indicator of seizures. Among witnessed seizures, 467 (81%) were spontaneous, and 112 (19%) were provoked by handling and/or ketamine administration. Seizures are usually brief: the median duration is 40s (range 5[ndash]300s, n = 134). Seizures are most common during the morning hours (68%, n = 314). Seizures are equally distributed between the sexes (212 F, 232 M) and sex-specific age distributions are similar. Seizures are observed at all ages, but are most prevalent in younger animals[mdash]about 40% of cases are younger than 4yr, and about 60% of cases have their first seizure prior to reaching adulthood (6[ndash]7 yr). There is no significant difference in the subspecies prevalence of seizure. These data help establish the baboon as a valid nonhuman primate animal model for idiopathic generalized epilepsy in humans. The prevalence of seizures in the baboon population is much greater than can be expected in a comparable human sample, and the epidemiological features of the seizures in the colony are similar to those seen in human populations. The availability of accurate pedigree information for the baboon colony enables quantitative genetic analysis to identify genetic contributions to seizures and related traits. (Supported by NIH/NINDS grant NS047755.)