INHERITANCE OF ALLERGY 



321 



students of the inheritance of allergic diseases. Except for the works of 

 Adkinson and Buchanan the types of allergy have been considered as due 

 to dominant factors. Adkinson's results can be explained as due to a 

 dominant gene, dependent for its expression to some extent upon the envi- 

 ronment. Migraine has been regarded as a sex linked character by several 

 writers because of the large number of females who have it. However, we 

 have shown that migraine may be inherited by the son from the father when 

 the mother's line is negative and therefore cannot be sex linked. Also 

 migraine is interchangeable with the other allergies and acts as the expres- 

 sion of the same gene for sensitivity which obviously has no connection 

 with sex. Since allergic women are apt to suffer from these headaches 

 during the menstrual period (a fact which has been referred to a number of 

 times in the literature and which we also have observed) the preponderance 



TABLE 2* 



See table 1 for meaning of letters. (— ) no allergy. 



of migraine females can best be explained as correlated in some way with 

 the sex hormones and with physiological processes. Finally we have found 

 no connection (as did Study and Gansslen) between gout and the allergic 

 diseases mentioned. 



We have shown that any allergy may act as a simple dominant, and an 

 allergic individual may transmit either the same or another type of allergy. 

 There is thus no regularity in the transmission of the different types of 

 allergy and the individual known to carry the gene for sensitivity may be 

 normal. Our evidence thus shows that most probably allergy is not due 

 to multiple factors, but rather to the expression of a single gene for sensi- 

 tivity which manifests itself in different ways, depending to some extent 

 upon the environment of the individual. The gene for allergy is not sex 

 linked. The greater number of migraine females cannot be explained as 

 due to a sex linked gene. 



