Five of the melanoma cases were PITX1-positive (melanoma tissue sample number 1, 5, 6, 7, 8) and nine cases were PITX1-negative (melanoma tissue sample number 2, 3, 4, 9, 10, 11, 12, 13, 14) (Fig. 3C and D). Here, PITX1 is linked to melanoma.