Lung function in the children of immigrant and UK-born south-Asian mothers

There are ethnic differences in lung function, with white subjects having larger height-normalised forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) than black people or Asians [1, 2]. It has been argued that these differences might be explained by environmental and social factors associated with poverty [3, 4]. Alternatively, the differences in lung volume might be explained by inherent factors, such as genetically determined differences in body frame, with a relatively smaller thoracic cage and, consequently, smaller lungs in some Asian ethnic groups [4, 5]. If the differences were explained mainly or entirely by environmental exposures, lung function in populations migrating from a south-Asian to a western European country should increase in successive generations as standards of living gradually approach those of the host region.