Fig. 2: TERT alterations arise during the earliest progression stages.

a Amplifications, upstream structural rearrangements, and promoter mutations of TERT all occurred on the trunk of phylogenetic trees and invariably were identifiable in the earliest progression stage of melanomas that carried these alterations. The relative frequency of the different types of TERT alterations are shown. b An example case with structural rearrangement immediately upstream of TERT (left) shared across all three tumor areas from two different progression stages. The corresponding phylogenetic tree is shown (right). Source data are provided as a Source Data file.