Genetics

Front 1

Which protein is responsible for mRNA synthesis?

Back 1

RNA Polymerase II

Front 2

Protein needed for HIV mRNA transcription

Back 2

Tat

Front 3

Is there a cis-acting consensus sequence in DNA that signals termination?

Back 3

No

Front 4

A regulatory protein considered "guardian of the genmoe" because it prevents S phase entry unless DNA is in order.

Back 4

p53

Front 5

How the "guardian of the genome works"...

Back 5

p53 inhibits cell cycle kinases and encourages pro-apoptotic genes when appropriate.

Front 6

What is one of the major proteins responsible for acetylating histones for activation into S phase? How is it normally regulated?

Back 6

E2F, regulated by Rb (when phosphorylated by cell cycle kinases, dissociates from E2F, allowing E2F to promote transcription of machinery that perpetuates the cell cycle)

Front 7

Describe Rett Syndrome

Back 7

Brought on by a mutation that leads to overexpression of certain genes. The MeCP2 gene is dysfunctional and not able to recognize its target of methylated cytosene and then unable to bind HDAC, which would suppress the gene.

Front 8

Describe Prader Willi Syndrome

Back 8

imprinting of the maternal gene in addition to deletions on the father's allele leads to selective expression of defective proteins

Front 9

What inhibits Cyclin D (cell cycle kinases)?

Back 9

p16INK4

Front 10

Describe the splicing process

Back 10

RNA Pol and CPSF/CstF (both phosphorylated) recognize signal in DNA that leads to splicing and addition of the polyA tail (no consensus sequence for termination)

Front 11

snRNPs

Back 11

small ribonuclear proteins with catalytic action

Front 12

non-snRNP Proteins

Back 12

regulatory pre mRNA splicing factors

Front 13

Explain the splicing mechanism

Back 13

a) binding of snRNPs to consensus sites, via base pairing
b) assembly of spliceosomes brings players into appropriate position
c)endonucleolytic attack (formation of lariat loop structure)

Front 14

name three types of mutations that can occur in the B-globin chain

Back 14

a)single NT changes that destroy normal splice sites and activate cryptic splice sites
b) destroy normal splice site causing exon plicing
c) create new splice sites causing new exons to be incorporated

Front 15

Name post-transcriptional modification to tRNA

Back 15

tRNA transcribed by pol III
a) internal promoter elements of initiation
b) removal of intron (different splicing from mRNA--no lariat--2 cuts then ligation)
c) addition of CCA to 3' end (acceptor of amino acid)
d) processing of 5'end (by RNaseP)

Front 16

Explain how RNAi's work

Back 16

small dsRNA, 21-25NT's long that bind target mRNA and cause degredation or interfere with translation

Front 17

Define characteristics of Alkaptonuria

Back 17

rare autosomal recessive; urine turns black with exposure to air

Front 18

G6PD A deficiency

Back 18

G6PD A is an unstable protein that has a much shorter half life and causes RBC's to selectively heomlyze. Blacks affected

Front 19

A1AT

Back 19

Protease inhibitor (Pi, mutant Pi ZZ) that inhibits neutrophil elastase, especially in the lung.

Front 20

name the cellular components in translation

Back 20

a) nucleolus (organizing center of translation that produces rRNA, ribosomal units assemble)
b) ribosomes (small unit with the Met and elF-2, and the large that completes the protein synthesis)
c) amino-acyl tRNAs bind specific AA's to ribosome
d) ribosome moves along, elongating the protein

Front 21

What are the results of a thalassemia?

Back 21

inclusion of B4 (HGH)

Front 22

What are the results of B thalassemia?

Back 22

deficiency in B chain is dangersous due to precipitation of a4 chain very insoluble leading to destruction of RBC's in marrow and spleen

Front 23

Define HPFH

Back 23

hereditary persistence of fetal hemoglobin caused by mutation in B globin gene cluster

Front 24

a-/aa

Back 24

heterozygous a thalassemia silent carrier

Front 25

--/aa

Back 25

heterozygous a thalassemia 1

called a thal traint

Front 26

a-/a-

Back 26

a thalassemia 1 phenotype in blacks. homozygous thalassemia 2 a thal trait

Front 27

a-/--

Back 27

HbH disease (B4)

Front 28

--/--

Back 28

hydrops fetalis with Hb Barts (=gamma4)

Front 29

what is the frequency of the mutant allele for X-linked diseases?

Back 29

q=frequency of males affected
q^2 is frequency of carrier females

Front 30

What are the factors of a collecting a genetic history?

Back 30

-Make it relevant to the HIP (History of Present Illness)
-Ask specifically about 1st degree relatives
-Ask about informative relatives
-Ask about early-onset, preventable illness
-keep up-to-date
-Record ethnic/ancestral background, where relevant
-Inquire about consanguinity, where relevant

Front 31

Name elements of Genetic counseling

Back 31

-Nonjudgmental and not directive
-Candor (freedom from prejudice or malice) and honesty
-Communication and information transfer (spend time)
-Social and other support services
-Team effort (physician geneticists and genetic counselors) to promote patient autonomy and psychosocial adjustment

Front 32

What are the 2 types of genetic screening?

Back 32

Test I: Early recognition of affectid individuals where early intervention is of benefit to affected individual and/or family
Test II: identification of individuals at risk of transmitting genetic disease

Front 33

Name the criteria for a successful genetic screening program

Back 33

-Clinically significant disease that warrants screening
-High-risk population
-Inexpensive test with adequate sensitivity and specificity
-definitive test for specific diagnosis)—a gold standard (not the screen) that exists
-reproductive options available -counseling and education