Quantitative real-time PCR analysis of DDR1 and DDR2 expression performed on the 146 NSCLC tumour samples (full data set available as Supplementary Table S1) showed neither DDR1 nor DDR2 were associated with factors such as tumour stage (P=0.38 and P=0.51, respectively), differentiation (P=0.93 and P=0.60, respectively), and age (Spearman's correlation P=0.82 and P=0.48, respectively). The gene discussed is DDR2; the disease is non-small cell lung carcinoma.