Mutations
what are 3 trans mutations where there is a single base pair substitution?
silent, nonsense, missense
What is the end result of meiosis?
4 haploid cells (n) are produced that are genetically different from the parent cell
DNA sense 5' ATG GCG TAC CGC 3'
DNA antisense = ?
mRNA = ?
DNA antisense = 3' TAC CGC ATG GCG 5'
mRNA = 5' AUG GCG UAC CGC 3'
What is 47, XXY called?
Kleinfelters
Compare 'A' and 'a' in Autosomal Recessive and Autosomal Dominant
Auto. Recessive = 'A' is normal and 'a' is LOF
Auto. Dominant = 'A' is GOF and 'a' is normal
What does the cis region code for?
What is the end result of mitosis?
two daughter cells are produced that are genetically identical to the parent
What type of mutation is this?
sense strand 5' ATG CGC TAC CAC 3'
Mutated sense 5' ATG CGC ATA CCA C 3'
Frameshift
What is Turners?
45, X
A man's father has sickle cell anemia. His mother does not and is not a carrier. The man has children with someone who has the disease. What is the chance that they will have 3 kids in a row that are carriers? What is the chance that they will have a child that has 2 normal alleles?
1/8
0
The open reading frame is disturbed. What mutation is causing this? Where is it occurring?
Frameshift. Trans sequence.
Where do tetrads occur?
Prophase I of meiosis
What type of mutation is this?
Sense strand 5' ATG TAC GAG CGA 3'
Mutated sense 5' ATG TAT GAG CGA 3'
Silent
What is 47, XYY
Jacobs
Compare Independent Segregation and Independent Assortment
Segregation = For every genomic locus we have two alleles. These alleles segregate independently of one another
Assortment = The alleles of two different traits assort independently of one another due to crossing over
A trans mutation has occurred. Which of the following is a situation that can occur?
(a) A normal protein is produced, but it is now being produced in adulthood when it should only be produced in embryonic life
(b) A protein ends too early due to a stop codon being placed too early in the sequence via a single nucleotide substitution
(c) A normal protein is produced, but too much is being produced
(d) A protein is being produced in the kidneys when it should only be produced in the blood
b
compare sister chromatids and homologous chromatids
homologous chromatids = one chromatid from each parent - genetically different
sister chromatids = result of duplication - these are identical to one another
What type of mutation is this?
Sense strand 5' ATG TAC TAT GAG 3'
mutated Sense 5' ATG TAC TAA GAG 3'
Nonsense
Compare nondisjunction in anaphase I and II
Nondisjunction in anaphase I results in 2 gametes with too much DNA and 2 gametes with not enough
Nondisjunction in anaphase II results in 2 normal gametes, 1 with too much DNA, and 1 with not enough
Look at diagram 1. What is the genotype of individual II-1? If II-1 and II-2 have another kid, what is the probability that it will be phenotypically normal? If the kid is phenotypically normal, what is the chance that it will be a carrier?
Carrier (Aa)
3/4
2/3
A LOF cis mutation has occurred. Which of the following is a situation that can occur?
(a) A nonsense mutation causes the protein to stop prematurely
(b) The correct protein is being made, but it is only supposed to be made in embryonic life and now it is being made in an adult
(c) The correct protein is being made, but it is supposed to be produced in 5 different tissues. Now it is only being produced in 1
(d) A missense mutation occurred
c
When do homologous chromatids pair up? What are these called?
In prophase I of meiosis. Tetrads
What type of mutation is this?
Sense Strand 5' ATG TAC TAT GAG 3'
Mutated sense 5' ATG TAC TAT GAC 3'
Missense
What is happening in diagram 3
Trisomy 21
Look at diagram 2. Individual III-6 marries someone who has the disease. What is the chance that they have a living kid without the disease?
1/3