[Genetics of bronchial asthma with reference to allergy]

No uniform opinion exists to date in respect of the transmission of a genetic disposition to asthma bronchiale and atopy. Literature references discuss both monogenic, autosomal dominant or recessive and multifactorial-polygenic heredity. The following contribution discusses the results of an own study on the occurrence of atopy and asthma bronchiale in 153 families. Multifactorial-polygenic heredity with threshold value range is most suitable for the interpretation of our findings, even though an autosomal dominant heredity with reduced penetrance and variable expressivity might well be the basis for the transmission of a disposition to atopy and asthma bronchiale. In multifactorial-polygenic heredity with threshold value range, empirical risk data are important for predicting the disease risk. Such data can be obtained only on the basis of extensive family research and apply only to the population for which they were obtained. The risk of occurrence of atopy or asthma bronchiale in families already affected by the increases, in our experience, with the number of the patients already suffering from the disease and with the closeness of relationship with the patients concerned. We found a recurrence risk for further children of 40-45% for atopy and of 5-10% for asthma bronchiale in those marriages where both one parent and already one child are suffering from the disease.