MODY 1 is a form of maturity onset diabetes of the young

Maturity onset diabetes of the young

Maturity onset diabetes of the young refers to any of several hereditary forms of diabetes caused by mutations in an autosomal dominant gene disrupting insulin production...

.

MODY 1 is due to a loss-of-function mutation in the gene on chromosome 20

Chromosome 20 (human)

Chromosome 20 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 20 spans around 63 million base pairs and represents between 2 and 2.5 percent of the total DNA in cells...

. This gene codes for HNF4-α protein also known as transcription factor

Transcription factor

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow of genetic information from DNA to mRNA...

 14 (TCF14). HNF4α controls function of HNF1α (see MODY 3; ) and perhaps HNF1β (MODY 5) as well. This transcription network plays a role in the early development of the pancreas, liver

Liver

The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...

, and intestine

Intestine

In human anatomy, the intestine is the segment of the alimentary canal extending from the pyloric sphincter of the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine...

s. In the pancreas these genes influence expression of, among others, the genes for insulin, the principal glucose transporter

Glucose transporter

Glucose transporters are a wide group of membrane proteins that facilitate the transport of glucose over a plasma membrane. Because glucose is a vital source of energy for all life these transporters are present in all phyla...

 (GLUT2

GLUT2

Glucose transporter 2 also known as solute carrier family 2 , member 2 is a transmembrane carrier protein that enables passive glucose movement across cell membranes. It is the principal transporter for transfer of glucose between liver and blood, and for renal glucose reabsorption...

), and several proteins involved in glucose and mitochondrial metabolism.

Although pancreatic beta cells produce adequate insulin in infancy, the capacity for insulin production declines thereafter. Diabetes (persistent hyperglycemia) typically develops by early adult years, but may not appear until later decades. The degree of insulin deficiency is slowly progressive. Many patients with MODY 1 are treated with sulfonylureas for years before insulin is required.

Liver effects are subtle and not clinically significant. Many people with this condition have low levels of triglyceride

Triglyceride

A triglyceride is an ester derived from glycerol and three fatty acids. There are many triglycerides, depending on the oil source, some are highly unsaturated, some less so....

s, lipoprotein(a)

Lipoprotein(a)

Lipoprotein is a lipoprotein subclass. Studies have identified Lp as a putative risk factor for atherosclerotic diseases such as coronary heart disease and stroke....

, apolipoprotein

Apolipoprotein

Apolipoproteins are proteins that bind lipids to form lipoproteins and transport the lipids through the lymphatic and circulatory systems....

s AII and CIII.

Mutations in the alternative promoter of HNF4A are linked to development of type 2 diabetes.