Intravenous injection of GFP-labelled BxPC3 primary tumour cells containing sgRNAs targeting the 3′ splice sites of MYL6 or CLSTN1 into NOD-SCID mice revealed a significant increase in the number of lung metastatic foci, compared with cells with a control sgRNA targeting MYL6 (Extended Data Fig. 11g), with a slight, nonsignificant effect for CLSTN1 (Extended Data Fig. 12g). The gene discussed is CLSTN1; the disease is neoplasm.