A unique pedigree is presented which shows tuberous sclerosis in three generations of a family, in which two heterozygotes for the mutant gene were found to be clinically asymptomatic. A genetic model is proposed to explain these findings based upon the segregation of a second unlinked autosomal dominant gene modifying the expression of the gene for tuberous sclerosis.

1364 From late 1930, lethal genes have been used as ge netic markers to detect concealed variation in Droso phila populations [1–4]. In order to study lethal genes a lethal balanced strain is required. This strain is a ge netic construction involving a pair of homologous chromosomes with the following characteristics: they have to contain natural or induced chromosomal in versions to block reco...

conclusions congenital hyperinsulinism can have different inheritance pattern. autosomal recessive inheritance is more common but less frequently autosomal dominant inheritance can be seen. it appears that mutations in abcc8 gene can show both autosomal recessive and autosomal dominant inheritance of the disease. pcr followed by sanger sequencing proved to be an efficient method for mutation de...