Reports of the successful treatment of DOCK8 deficiency through HSCT from human leukocyte antigen (HLA)-matched siblings or unrelated donors have been published.[18–20] More recently, HSCT from haploidentical related donors using post-transplantation cyclophosphamide has been found to be effective in patients with DOCK8 deficiency who lack a fully HLA-matched donor. Here, DOCK8 is linked to hyperinsulinemic hypoglycemia, familial, 4.