One subphenotype was the moderate AD group with negative SPT and preserved lung function (subphenotype 1, n = 158), one was the high AD group with positive SPT and airway hyperresponsiveness (subphenotype 2, n = 300), and one was the low AD group with positive SPT and lower lung function (subphenotype 3, n = 753). This evidence concerns the gene AGXT and airway hyperresponsiveness.