Recently, Lenglet et al., 2018 identified a new VHL cryptic exon termed E1' deep in intron 1 that is naturally expressed in many tissues, and found E1' mutations in eight families with either erythrocytosis or VHL disease. The goal of this study was to determine the prevalence of E1' germline mutations from two cohorts, 221 patients with a single or multiple tumours, suggestive of VHL disease, and 946 patients with a Pheochromocytoma/paraganglioma (PPGL) but without an identified mutation in the three VHL exons or in the main PPGL susceptibility genes. They identified a rare germline genetic variant (maf <1%) in the E1’ VHL cryptic exon in 1% of patients (12/1167). Patient 11 was diagnosed at the age of 12 due to multiple head and neck paragangliomas, and was found to have a rare germline c.340+725A>T E1' variant.