Hyperinsulinism-hyperammonemia syndrome explained

Synonyms:	HI/HA or HHS
Causes:	mutations of the GLUD1 gene

Hyperinsulinism-hyperammonemia syndrome (HI/HA) is an autosomal dominant disorder that results in the excess production of insulin and ammonia in mammals.^[1] HI/HA is caused by increased Glutamate dehydrogenase 1 (GDH) activity due to the presence of overactivating point mutations in GDH. These point mutations either directly or indirectly prevent guanosine triphosphate (GTP) binding and inhibition of GDH, which causes GDH to uncontrollably remain active.^[2]

External links

• Familial hyperinsulinemic hypoglycemia-6 (HHF6) - entry in the OMIM database

Notes and References

1. Pinney. SE. MacMullen. C. Becker. S. Lin. YW. Hanna. C. Thornton. P. Ganguly. A. Shyng. SL. Stanley. CA. Clinical characteristics and biochemical mechanisms of congenital hyperinsulinism associated with dominant KATP channel mutations.. The Journal of Clinical Investigation. August 2008. 118. 8. 2877–86. 10.1172/JCI35414. 18596924. 2441858.
2. Smith. Hong Q.. Smith. Thomas J.. Identification of a Novel Activator of Mammalian Glutamate Dehydrogenase. Biochemistry. 2016. 55. 47. 6568–6576. 10.1021/acs.biochem.6b00979. 27808506.