As DAXX and ATRX are localized in the telomeric regions of embryonic chromosomes, it cannot be excluded that in embryogenesis, DAXX and ATRX are involved in the Alternative Lengthening of Telomeres (ALT), especially since mutations in the DAXX gene have been described in patients with telomerase-negative pancreatic neuroendocrine cancers [65]. The gene discussed is ATRX; the disease is pancreatic endocrine carcinoma.