Based on the calculated coordinates of ROC curves, we propose a threshold of 1.22 (sensitivity 92.3%, specificity 89.6%, Fig. 3E) for detection of ALT by telomere content, and a threshold of 9.01 kb (sensitivity 87.5%, specificity 85.7%, Fig. 3F) for detection of ALT by telomere length in independent neuroblastoma cohorts (Additional file 3: Tab. Here, GPT is linked to neuroblastoma.