Three whole-exome sequencing studies performed on patients with sporadic PAs, both on tumor specimens and the corresponding blood-derived genomic DNA, confirmed the MEN1 gene as the most common mutated/loss in sporadic PAs at the somatic level, and identified novel mutated genes that may represent low-frequency driver mutations in parathyroid tumorigenesis [32,34,35]. Here, MEN1 is linked to neoplasm.