TYK2 and cancer: In our targeted re-sequencing approach, 39 genes were included that were not causally linked to cancer, but were selected as candidate oncogenes or tumor suppressor genes, because of their function (e.g., tyrosine kinases and tyrosine phosphatases) or because family members had been implicated in cancer (e.g., TYK2 for the JAK family, TET1 because TET2 is a known cancer gene).