Diabetes Flashcards
What causes MODY (maturity onset diabetes of the young)?
Autosomal dominant mutation
HNF 4alpha
HNF 1alpha
Glucokinase
HNF 1alpha
Transcription factor that stimulates insulin production
Mutation = insulin production decreases in adulthood when its function naturally deteriorates
Treatment for HNF 1alpha MODY
Metformin = cells more sensitive to insulin Sypulphonylurea = stimulates pancreas to produce more insulin
What is glucokinase MODY?
Enzyme converts glucose - G6P
Higher glucose conc needed for insulin secretion to occur
Patients have stable mild hyperglycaemia
HNF4alpha MODY
Similar to HNF1alpha but rarer
Older onset
Low renal glucose threshold
HNF1beta MODY
Renal cysts and diabetes
Genital tract mutation
What mutation causes Permanent neonatal diabetes
KNCJ11
1 in 400000 births
Diabetes in first 6 months
How does the mutation cause permanent neonatal diabetes
KNCJ11 causes K+ channel to open when ATP is made by respiration
This means membrane cannot be hyper polarised and insulin not released
How do sulphonylureas treat PND?
Close the K+ channel so signal sent to insulin to be released
What is Sanger sequencing?
Sequences all exons of one single gene
Used to identify unknown mutation
Very precise
But expensive, time consuming, poorly automated
What is next generation sequencing?
Sequences multiple genes
Used to identify mutations in multiple genes for heterogenous phenotypes
Cost effective
Not very accurate, needs a lot of data to sequence
What is pathogenicity?
Ability for an organism to cause disease
Symptoms of maternally inherited diabetes and deafness (MIDD)
Young onset deafness
High lactate
Muscle aches
Short stature
What is polygenic diabetes?
Type 1 and 2
There must be a second hit to get condition e.g. environmental
What is GWAS?
Genome wide association study
Study to see if variations in gene have different traits
