Mutational profile of the 19 sporadic MTC cases diagnosed before 30 years old, identified by the somatic (top) and germline (bottom) exome. Each column corresponds to a single case. Genetic variations are listed on the left. The red squares correspond to pathogenic variants, whereas the blue squares correspond to variants of uncertain significance (VUS) for the MTC phenotype and the gray squares identify 4 cases without somatic exome analysis: tumor not available (1 case) and bad quality DNA (3 cases).