title: Frequency of tuberous sclerosis in San-in district (Japan) and birth weight of patients with tuberous sclerosis.
abstract: Fifty-two patients with tuberous sclerosis including 44 propositi were collected from 11 hospitals and 20 institutions in the San-in district. Of the 52 patients 44 were alive at the time of the study and the prevalence of tuberous sclerosis among the general population of the San-in district in October 1979 was estimated to be one in 31,000 (3.2 x 10(-5)), which was the highest value among the surveys in certain geographical areas. The frequency of tuberous sclerosis in live-births was estimated to be one in 24,000 (4.0 x 10(-5)). The frequency of the sporadic cases in live-births was one in 31,000 (3.2 X 10(-5) and the mutation rate was directly estimated to be 1.6 X 10(-5) per gene per generation. A difference between the parental age or birth order of the sporadic cases and those of controls was not detected. The mean birth weight for the tuberous sclerosis group was 2,834 g which was slightly less than the 2,985 g for their normal sibs. The frequency of low birth weight, less than 2,500 g, among the children with tuberous sclerosis was 30% (7/23), which was 4 times that in the general population (P less than 0.005). These facts suggest that the intrauterine growth is affected in a considerable number of the patients.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001722:Birth Order; D001724:Birth Weight; D002648:Child; D002675:Child, Preschool; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D010375:Pedigree; D014402:Tuberous Sclerosis / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics