Table 3.

Monogenic defects of insulin secretion

Genes	Function of the protein or tRNA	Phenotype of mutation carriers
HNF1A, HNF1B, HNF4A, PDX1, NEUROD1, KLF11, PAX4	Involvement in beta cell differentiation, proliferation and insulin synthesis	MODY, rarely PNDM if biallelic dysfunction
BLK	Non-receptor tyrosine-kinase regulating insulin synthesis	MODY
SLC2A2 (GLUT2)	Glucose transport to beta cell	Fanconi-Bickel syndrome
GCK	Glucose phosphorylation in the limiting step of ATP production in beta cell	MODY, PNDM if biallelic dysfunction
mitochondrial leucyl tRNA gene and several other mitochondrial genes	Mitochondrial ATP synthesis	MIDD
KCNJ1, ABCC8	Structure and function of the ATP-sensitive potassium channel of beta cells	PNDM, TNDM, MODY
INS	Coding for insulin	PNDM, MODY