TALDO1 and hyperinsulinemic hypoglycemia, familial, 4: Transaldolase (TALDO) deficiency (OMIM 606003), a rare metabolic congenital defect of the pentose phosphate pathway (PPP), is caused by homozygous or compound heterozygous variants of the TALDO1 gene (Wamelink et al., 2008) located on chromosome 11p15.