title: Bronchial reactivity pattern in nonasthmatic parents of asthmatics.
abstract: Genetic mechanisms have been proposed to explain the presence of asthma in families. A methacholine challenge can identify individuals with bronchial reactivity (a hallmark of asthma). It may then be possible to determine whether the presence of non-specific bronchial reactivity, as detected by a methacholine response, has potential as a genetic marker. Thirty-one non-asthmatic parent pairs of asthmatic children were selected from asthma (AF) families enrolled in a Natural History of Asthma study. Parent pairs were chosen if both gave negative responses to a modified National Heart, Lung and Blood Institute questionnaire on asthma. The methacholine response of these parents of asthmatic children had a bimodal distribution. These results show that the methacholine response can mark bronchial reactivity without the presence of clinical asthma and that a familial component of bronchial reactivity exists which may be transmitted from one generation to the next.
mesh_terms: D001249:Asthma / Q000235:genetics* / Q000503:physiopathology; D001980:Bronchi / Q000502:physiology*; D001985:Bronchial Provocation Tests; D005260:Female; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D008688:Methacholine Compounds; D010290:Parents
chemical_list: D008688:Methacholine Compounds; D016210:Methacholine Chloride