UCP2 and congenital isolated hyperinsulinism: Genetic testing did not reveal any disease-relevant pathologic variation in genes that are most frequently associated with CHI: ABCC8 (GenBank NM_000352.4), HADH (GenBank NM_005327.4), HNF4A (GenBank NM_175914.4), KCNJ11 (GenBank NM_000525.3), and UCP2 (NM_003355.2).