By David Fairchild Weeks, M.D.,
Medical Superintendent and Executive Officer, the New Jersey State Village for Epileptics at Skillman, U.S.A.
In this paper the writer has endeavoured to learn what laws, if any, epilepsy follows in its return to successive generations, and the relation it bears to alcoholism, migraine, paralysis, and other symptoms of lack of neural strength.
The data used in the study was analysed according to the Mendelian method which assumes that the inheritance of any character is not from the parents, grandparents, etc., but from the germ plasm out of which every fraternity and its parents and other relatives have arisen. If the soma possesses the trait of the recessive to normality sort, it lacks in its germ plasm the determiner upon which the normal development depends, and this condition is called nulliplex. If the soma possesses the trait of the dominant to normality sort, the determiner was derived from both parents and is double in the germ plasm, or normal, all of the germ cells have the determiner; or else it came from one parent only, is single in the germ plasm, or simplex, and half of the germ cells have and half lack the determiner.
The method of obtaining the data was by means of field workers, who interviewed in their homes the parents, relatives and all others interested in the epileptic patient. These visits have established a friendly feeling toward and an intelligent understanding of the Institution and its work.
The study is based on the data derived from 397 histories, covering 440 matings.
The matings are classified under the six possible types, of nulliplex × nulliplex, nulliplex × simplex, nulliplex × normal, simplex × simplex, simplex × normal, and normal × normal.
Under the first type all those matings where both parents were epileptic, one was epileptic and the other feeble-minded, or both were feeble-minded, are classified. According to Mendel's Law, all of the children should be nulliplex. The data showed all of the children defective.
Under the type nulliplex × simplex, all matings where one parent was epileptic or feeble-minded and the other "tainted," that is, alcoholic, neurotic, migrainous, or showed some mental weakness, are classified. From this type of mating, 50% of the offspring are expected to be nulliplex and 50% simplex. From the matings where one parent was epileptic or feeble-minded and the other alcoholic, there were 61% mentally deficient or nulliplex, the remainder simplex. The figures for the offspring from the other matings showed 47% nulliplex, and 53% simplex.
For the third type, nulliplex by normal, all those matings where one parent was epileptic or feeble-minded and the other reported as mentally normal are classified. From this type of mating, the expectations are that all of the children would be simplex. A study of the ancestors of the normal parents showed these parents simplex rather than normal. The analysis of the offspring showed at least 43% nulliplex, which is a close fitting to the type of mating nulliplex × simplex.
The fourth type of mating is simplex × simplex. Here, all matings where both of the parents were "tainted" are classified. The expectation is that 25% of the offspring would be nulliplex, in reality 35% were found to be mentally deficient.