Save
Busy. Please wait.
Log in with Clever
or

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever
or

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't know
Remaining cards (0)
Know
0:00
share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

GeneticDisorders-I

lecture 24 wilson

QuestionAnswer
# of base pairs in human genome ~ 3 billion bps
percent of spontaneous abortuses in early gestations that were due to genetic abnormalities up to 50%
# of genes in human genome 30,000 genes
what percent of human genome encodes proteins? < 2%
functional cloning one starts with the clinical phenotype and the enzyme that's affected and works backwards to clone the gene
positional cloning closer to the standard idea of cytogenetics, identification of possible genes by mapping to specific chr loci
examples of diseases that are treated with recombinant DNA technology erythropoietin for anemia, tPA for thrombotic episodes, myeloid factors for stimulating BM growth, TNF receptor for RA
examples of dz that is treated with gene therapy transplantation of a somatic cell that's been transfected with a normal gene, used in deaminase deficiency. downfall: hard to get the genes expressed in the right tissues
definition of mutation permanent change in DNA
3 categories of mutations 1) single gene mutations with large effects (sickle cell anemia) // 2) chr disorders (Down syndrome) // 3) complex multigenic disorders (HTN, multifactorial inheritance)
mechanisms of gene mutations missense (sickle cell anemia), nonsense (beta-thalassemia) and frameshift (normal generation of O blood group phenotype)
4 major categories of genetic dz disorders of mutant genes with large effect (Mendelian), multifactorial inheritance, chr disorders, non-classic/non-Mendelian inheritance
autosomal dominant inheritance pattern heterozygotes express phenotype of STRUCTURAL PROTEIN ABNORMALITY, @ least one parent is always affected, males and females affected equally and all can transmit
autosomal recessive inheritance pattern homozygotes express the phenotype of ENZYME DEFICIENCY (classically), trait doesn't effect parents who are carriers, 25% recurrence risk, associated with higher incidence of consanguinity
X-linked recessive inheritance pattern typical granfather --> grandson transmission, father makes all his daughter carriers, sons of heterozygous women have 50% risk of having dz
X-linked dominant inheritance pattern very rare, affected father transmits to all of his daughters but NONE of his sons, affected heterozygous mothers transmit with 50% chance to all children
4 categories of single gene or Mendelian disorders 1) defects in structural proteins // 2) defects in receptor, transmembrane proteins // 3) defects in enzymes // 4) defects in proteins regulating cell growth
Marfan syndrome defects in structural protein fibrillin, which serves as scaffolding for deposition of elastin. phenotype: subluxation of lens, tall stature with long ext/arachnodactyly, scoliosis, dilated aortic root, aortic dissections (up to whole body vol in wall)
cystic medionecrosis of aorta clinical feature of Marfan's syndrome, predisposition to hemorrhage within the walls of the aorta causing fusiform aneurysm
inheritance pattern of Marfan syndrome autosomal dominant with 20% of cases being due to new mutations
Ehlers-Danlos syndrome mostly AD dz typified by defects in structural protein collagen. phenotype: hyperextensible joints and skin, cigarette paper scars (from shallow scarring after defective repair), aortic rupture
CF AR dz characterized by defective CFTR (transmembrane protein) that doesn't regulate Na/H20 well causing mucus to be dehydrated and thick in the lungs, biliary tree & pancreas. traps bacteria in lungs = pneumonia. increased NaCl in sweat
positive sweat chloride test used to diagnose CF and determine clinical phenotype. if (+) then pt likely to have bronchiectasis, hepatic cirrhosis, pancreatic insufficiency and male infertility
negative sweat chloride test pt can still have CF but the more mild phenotype. azoospermia, sinusitis, absence of vas deferens (all as sole abnormalities)
genetic and environmental modifiers of CF severity CF modifer locus or CFM-1 = severity of meconium ileus, MBL-immunity for opsonization, virulence of infecting organism(s), exposure to smoking or other allergens
classification of mutations in CF can be due to defective protein synthesis, abnl protein folding, processing or trafficking, defective regulation, decreased conductance, reduced abundance, altered regulation of separate ions
Created by: sirprakes
Popular Genetics sets

 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
Retries:
restart all cards