TPSAB1 and hereditary disease: Hereditary α‐tryptasemia (HαT) is a recently identified, genetic disorder associated with elevated basal serum tryptase (BST) and multisystem, clinical phenotypes.1, 2, 3, 4 HαT is characterized by dominant inheritance of multiple copies of α‐tryptase‐encoding sequence for TPSAB1 leading to BST elevations.1, 2, 3, 4 The incidence of this genetic disorder is the subject of ongoing investigations.