Week 4 Prerecorded Genetics of Complex DIsease: Diabetes Flashcards
familial vs genetic
Genetic describes our DNA,. familial could be genetic, learned behavior, or environment
does Type I or Type II have a stronger familial component?
Type II (type II also has a strong genetic component)
Genetic risk factors: what are some rare diseases that can lead to diabetes? (4) Inheritance?
Cystic fibrosis, chronic pancreatitis, insulin receptor defects, pro-enzyme cleavage defects
(All autosomal recessive)
Genetic risk factors: what are some very rare diseases associated with development of diabetes?
mitochondrial disorders: MELAS, MNGIE (Auto rec, or maternal transmission)
Myotonic dystrophy: auto dominant. patient cant let go of your hand after shaking it
What is Maturity Onset Diabetes of the Young? cause? inheritance? Prevalence?
(MODY): Hypo-insulinism w/ gradual onset compared to type I DM. caused by LOF or dysfunciton of pancreatic B cells. Appears acutely like insulin depedent at older age. 1-2% of diagnosis of diabetes, Auto dom
Type I diabetes cause?
an autoimmune disorders; caused by mutations in Human leukocyte antigen gene complex
what is the human leukocyte antigen gene complex?
series of genes, some of which, are responsible for the antigens expressed by cells
which HLA alleles are associated with type I diabetes?
95% of type I DM have DR3 or DR4 (not sufficient for Type I diabetes)
DR3 allele product (antigen) is associated with? onset?
antibody against pancreatic Beta cells. later onset
DR4 allele product (antigen ) associated with? onset?
antibody against insulin. earlier onset
DR2 allele risk of diabetes?
Protective antigen, 30% decrease in risk for Type I diabetes
MODY 2: Cause? severity?
Associated with Glucokinase, mild glucose intolerance that can be well controlled with diet. Initially noted as gestational diabetes.
MODY Treatment
sulfonylureases are highly effective. not used to treat other non-MODY forms of diabetes
how does sulfonylureas fxn
increase intracellular calcium to increase release of pro-insulin (may also increase sensitivity of B cells to glucose)
MODY 1,3,4,5,6; presentation?
all present similarly as a delayed secretory response to glucose uptake that over-time (gradual) leads to hyperglycemia