A survey of Huttington's disease (HD) in Northern Ireland, with a population of 1.5 million, has shown a 1991 prevalence rate of 6.4/100 000.
Virtually complete ascertainement was achieved, enabling prevalence rate estimates and age statistics to be calculated over the last 20 years.
The prevalence rate is similar to the high prevalence rates of HD found in most European populations, suggesting the presence of either one extremely ancient or a number of separate mutational origins, resulting in a uniform European HD prevalence.
The ages at diagnosis and duration of the disease are similar to previous studies, suggesting a consistent effect of the HD gene in all families.
Estimates of heterozygote frequency (HF), direct and indirect mutation rate, fertility, and genetic fitness (W) were made.
Reliable HF estimates gave values between 10 and 11x10-5.
The direct and indirect mutation rates were 0.32x10-6 and 1.05x10-6 respectively.
W was increased in the affected HD population but decreased in the ar risk population.
Fertility in HD is not reduced, but it appears that at risk patients have actively limited their family size.
Factors responsible include, among others, the fear of developing HD and genetic counselling of families.
This is the first published epidemiological survey to include ascertainment data in a population both before and after isolation of the HD gene, and with the diagnosis in virtually all patients confirmed by DNA mutation testing.
Mots-clés Pascal : Chorée Huntington, Epidémiologie, Homme, Irlande, Europe, Système nerveux pathologie, Système nerveux central pathologie, Encéphale pathologie, Extrapyramidal syndrome, Maladie dégénérative, Maladie héréditaire
Mots-clés Pascal anglais : Huntington disease, Epidemiology, Human, Ireland, Europe, Nervous system diseases, Central nervous system disease, Cerebral disorder, Extrapyramidal syndrome, Degenerative disease, Genetic disease
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 95-0442479
Code Inist : 002B17G. Création : 01/03/1996.