MTAP and neoplasm: Three of the robust interactions involve genes frequently deleted with the tumour suppressor CDKN2A (CDKN2B and MTAP) and recapitulate known associations with CDKN2A. A further two genetic interactions involve a single chromosomal region (19p21.3) containing two interferon genes (IFNB1 and IFNW1) which are frequently deleted together and consequently these two interactions really represent a single association (an increased sensitivity to thrombopoietin receptor MPL).