MODY 4 or PDX1-MODY is a form of
maturity onset diabetes of the young.
MODY 4 arises from mutations of the
PDX1 homeobox
A homeobox is a Nucleic acid sequence, DNA sequence, around 180 base pairs long, that regulates large-scale anatomical features in the early stages of embryonic development. Mutations in a homeobox may change large-scale anatomical features of ...
gene on
chromosome 13
Chromosome 13 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 13 spans about 113 million base pairs (the building material of DNA) and represents between 3.5 and 4% of the total DNA i ...
. Pdx-1 is a transcription factor vital to the development of the embryonic pancreas. Even in adults it continues to play a role in the regulation and expression of genes for insulin, GLUT2, glucokinase, and
somatostatin
Somatostatin, also known as growth hormone-inhibiting hormone (GHIH) or by #Nomenclature, several other names, is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with G ...
.
MODY 4 is so rare that only a single family has been well-studied. A child born with
pancreatic agenesis (absence of the pancreas) was found to be
homozygous
Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism.
Mos ...
for Pdx-1 mutations. A number of older relatives who were heterozygous had mild hyperglycemia or diabetes. None were severely insulin-deficient and all were controlled with either diet or
oral hypoglycemic agents.
References
External links
Types of diabetes
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