In several clinical centres in Germany (Berlin, Hamburg, Munich and ot
hers) a collaborative study on the genetics of asthma is being perform
ed. It started at the beginning of 1995, when 100 nuclear families wit
h two or more affected siblings were recruited. The participants are b
eing characterized by interview information, methacholine challenge, p
eak flow variability, skin-prick test, total and specific IgE.