The association between single-nucleotide polymorphisms in PHF11 and asthma, or asthma-associated traits, has been investigated in many subsequent studies, with reports confirming the association in a number of ethnic populations.3, 4, 5 It is notable, however, that two studies have failed to replicate the original finding6, 7 potentially due to true differences in the effect of PHF11 variants between groups (e.g. due to variation in environmental exposures or through epistatic or gene–environment interactions) and variance in the patterns of LD between typed and true causative variants. This evidence concerns the gene PHF11 and asthma.