TGFBR1 and non-small cell lung carcinoma: The Int7G24A variant causes a G → A transversion in the +24 position of the donor splice site in intron 7 of TGFBR1. Although the functional role of this variant is still to be elucidated, Int7G24A has been found to increase the risk of kidney and bladder cancer and homozygous carriers have more than 3-fold increased risk of developing non-small-cell lung cancer (NSCLC) (Zhang et al, 2003; Chen et al, 2004).