Beta-1,3-glucuronyltransferase 3 (B3GAT3) deficiency [OMIM:245600], also known as Larsen-like syndrome, is a rare AR and idiopathic CDG with a mutation in the B3GAT3 gene on chromosome 11q12.3 [14]. This evidence concerns the gene B3GAT3 and hyperinsulinemic hypoglycemia, familial, 4.