Recombinant DNA Technology
What is PCR? Make a 5-nucloetide long primer for the below DNA and tell me the direction.
3' TAAGCTACGGTAGCT 5'
Polymerase chain reaction
Rapid method of DNA cloning that eliminates the need to use host cells for cloning.
5' ATTCG 3'
What are UV's three impacts on phenotypes?
Causes mutations, breaks down folate which causes defects in embryonic development, and increases amount of Vitamin D which is crucial for calcium intake.
What is the multiple gene hypothesis? What are additive alleles?
Multiple genes are individually behaving in Mendelian Fashion. They also contribute to the pentode in a cumulative way.
Contributes equally to red grain color.
Imagine you have a female individual with XX chromosomes. Label each chromosome X1 and X2. Create a diagram on how these chromosomes will align in metaphase 1 of meiosis and metaphase of mitosis.
Meiosis: x1x1 | x2x2
Mitosis: X1 | X1
X2 | X2
What are the limitations of PCR?
–Some information about nucleotide sequence of target D N A is required to synthesize primer
–Minor contamination from other sources can cause problems (e.g., skin cells from researcher)
–PCR cannot amplify long segments of DNA
What is the difference between Pleiotropy and Polygenic Inheritance?
Pleiotropy is when a single gene controls multiple traits and polygenic is when multiple genes control a single trait.
Bonus: What are examples of each?
What are transgenic and knock-out animals?
Transgenic is knock-in animals. They express of overexpress a gene. Knock-out animals is a gene that is repressed.
If a mitochondrial DNA mutation is discovered in a egg-bearing parent but not in her child, what is the most likely explanation?
The mother has heteroplasmy and the mutated mitochondria were not passed to the child.
What is RT-PCR and qPCR?
•Reverse transcription PCR (RT-PCR)
–Methodology for studying gene expression (mRNA production by cells or tissues)
–Reverse transcriptase is used to generate ds-cDNA
•Quantitative real-time PCR (qPCR)
–Real-time PCR allows researchers to quantify amplification reactions as they occur in real time
What is the difference between continuous and discontinuous variation? What genes control each type of variation?
Continuous Variation:
Discontinuous Variation:
Select all that apply. What type of mutations could most likely lead to a reduction in the amount of RNA that is transcribed.
A. Nonsense
B. Silent
C. Frameshift
D. Enhancer
E. Splice Site
Bernot says only D but I remember when I talked to her she said E is good as well.
You are following the inheritance of two genes linked on the same chromosome. Christian is heterozygous for both, AaZz. Christian has a haplotype of Az/aZ
The two genes are 4 cM apart. If you looked at hundreds of sperm that Christian produced, what is the frequency of the Az sperm?
48%
What is CRISPR-Cas9?
•CRISPR (clustered regularly interspaced palindromic repeats)-Cas system
•Gene editing method that involves the use of specifically engineered D N A-modifying enzymes (nucleases) that create changes in a specific sequence to remove, correct, or replace a defective gene or parts of a gene
•Gene editing is based on using different nucleases to create breaks in the genome in a sequence-specific manner
What are some polygenic traits that DON'T show continuous variation?
Meristic traits: Phenotype can be recorded by whole numbers. Number of seeds in pod and number of eggs laid by chicken.
Threshold traits: Has a small number of phenotypic classes. Type 2 diabetes.
In polygenes, what is the ratio of individuals expressing either extreme phenotype. Number of polygenes = n.
1/4^n
The MGMT protein is found at a lower level in glioblastoma cancer cells than in normal cells, due to methylation of the MGMT gene promoter sequence. To alter methylation states, you target methyltransferase, an enzyme that activates methylation. You introduce into the cancer cells an siRNA that has exact complementarity to the methylatransferase mRNA.
How would methyltransferase mRNA levels and methyltransferase enzyme levels be impacted?
Both would decrease.
What is the CRE-Lox system?
What is concordance? In what studies is this value usually studied?
When a set of twins have the same expression in a trait. Usually used in twin studies. Can show the potential value for heritability assessment.
"Wacking" is a paternally imprinted gene that, when expressed, ducks say "wack" instead of "quack." The gene of wacking is represented by w. Steve is a male duck who expresses this wacking gene. Steve's dad has the genotype W*W while Steve's mother has the genotype Ww*.
What is Steve's phenotype and potential gametes?
W*w
Gametes: W* w*
Hardy Weinberg Question 17
0.0349