Abstract
In an attempt todefine the mode of inheritance and the trait inherited, the genetic data were analyzed on 307 febrile convulsive children, who were divided into two groups, i.e., simple type (131 patients) and complicated type (176 patients). There was a tendency offamiliar aggregation and the contribution of genotype was suggested.
The mode of inheritance was considered as the multifactorial inheritance from the following results.
1. The rate of the incidence of febrile convulsions in sibs (19.86%) to that in the general population (2.9%) was approximately equal to the expected ratio from the multifactorial inheritance system.
2. The incidence in sibs showed the increasing tendency as those in parents and near relatives increased. The incidence in the second child increased with that in parents when thefirst child was affected in the family with two children.
3. The incidence in sibs increased with the in-creasing frequency of convulsion in proband.
4. According to Falconer's procedure, the heri-tability of liability was estimated as 76%, sugge-sting that the genotype was highly associated with the liability.
The above results were distinctly observed in the simple type, but less clear in the complicated type.
