RETREG1 and asthma: The discovery of potentially protective alleles in three genes, FAM134B (family with sequence similarity 134, member B1), NPC1L1 (Niemann-Pick disease, type C1, gene-like 1) and IKZF1 (IKAROS family zinc finger 1), is intriguing because elucidating the function of these variants could identify novel therapeutic targets for asthma.