In a genomic profiling study with biliary tract cancers which included 101 dCCA samples, researchers identified that a 350-kb region at 17q12 was amplified in 32.6% samples, containing known oncogene TBC1D3 and cytokine genes CCL3L3 and CCL4L2. Event of amplification of 17q12 showed disease-free survival hazard ratio of 1.36 and overall survival hazard ratio of 1.46.7 Here, CCL4L2 is linked to biliary tract cancer.