Some sources make a distinction between two forms of monogenetic diabetes:<unk>  and neonatal diabetes. However, they have much in common and are often studied together. Heterozygous<unk>  is inherited in an autosomal dominant fashion, and most patients therefore have other members of the family with diabetes; penetrance differs between the types (from 40% to 90%). Type OMIM Gene/protein Description<unk>  1 hepatocyte nuclear factor 4α Due to a loss-of-function mutation in the HNF4α gene. 5%–10% cases.<unk>  2 glucokinase Due to any of several mutations in the GCK gene. 30%–70% cases. Mild fasting hyperglycemia throughout life. Small rise on glucose loading. Patients do not tend to get diabetes complications and do not require treatment outside of pregnancy.<unk>  3 hepatocyte nuclear factor 1α Mutations of the HNF1α gene (a homeobox gene). 30%–70% of cases. Most common type of<unk>  in populations with European ancestry. Tend to be responsive to sulfonylureas. Low renal threshold for glucose.<unk>  4 insulin promoter factor-1 Mutations of the IPF1 homeobox (Pdx1) gene. ATP channel. ABCC8 Some forms of neonatal-onset diabetes are not permanent. < 1% cases. Tend to respond to sulfonylureas. Homozygous By definition, the forms of<unk>  are autosomal dominant, requiring only one abnormal gene to produce the disease; the severity of the disease is moderated by the presence of a second, normal allele which presumably functions normally. However, conditions involving people carrying two abnormal alleles have been identified. Unsurprisingly, combined (homozygous) defects of these genes are much rarer and much more severe in their effects. *MODY2: Homozygous glucokinase deficiency causes severe congenital insulin deficiency resulting in persistent neonatal diabetes mellitus. About 6 cases have been reported worldwide. All have required insulin treatment from shortly after birth. The condition does not seem to improve with age. *MODY4: Homozygous IPF1 results in failure of the pancreas to form. Congenital absence of the pancreas, termed pancreatic agenesis, involves deficiency of both endocrine and exocrine functions of the pancreas. Homozygous mutations in the other forms have not yet been described. Those mutations for which a homozygous form has not been described may be extremely rare, may result in clinical problems not yet recognized as connected to the monogenic disorder, or may be lethal for a fetus and not result in a viable child.
Maturity onset diabetes of the young
Ketosis-prone diabetes
Leucine-sensitive hypoglycemia of infancy
Cystic fibrosis–related diabetes
Lipoatrophic diabetes
Diet in diabetes
Kosaki overgrowth syndrome
Idiopathic hypoglycemia