CDKN1B and multiple endocrine neoplasia type 4: A typical multigene panel may include molecular analysis for germline mutations in hyperparathyroidism jaw tumor syndrome (CDC73); familial hypocalciuric hypercalcemia 1, 2, and 3 (FHH1, FHH2, and FHH3 from CASR, GNA11, AP2S1); familial isolated pituitary adenoma (with AIP accounting for 20%-30% of cases (6)); multiple endocrine neoplasia type 2 (RET); and, more recently, multiple endocrine neoplasia type 4 (MEN4, CDKN1B) (7, 8).