Week 1: Molecular Genetics

Question 1

Stages of cell cycle

Answer 1

G1, S, G2, M

Question 2

Steps of Mitosis

Answer 2

Prophase, Metaphase, Anaphase, Telophase

Question 3

Epigenetics

Answer 3

Heritable, reversible changes in gene function without change in DNA sequence

Question 4

Imprinting

Answer 4

Differential expression of alleles at a single locus, depending on whether the allele is inherited from mom or dad

Question 5

Point Mutation

Answer 5

Base substitution in which one bp is altered

Question 6

Silent Mutation

Answer 6

Change in nucleotide without change in aa

Question 7

Missense Mutation

Answer 7

Change in aa (may/not affect protein function)

Question 8

Nonsense Mutation

Answer 8

Introduce a premature stop codon

Question 9

Sensitivity Calculation

Answer 9

True Positives/ (True Positives + False Negatives)

Question 10

Specificity Calculation

Answer 10

True Negatives/ (True Negatives + False Positives)

Question 11

Positive Predictive Value Calculation

Answer 11

True Positives/ (True Positives+False Positives)

Question 12

Negative Predictive Value Calculation

Answer 12

True Negatives/ (True Negatives + False Negatives)

Question 13

Inheritance of Dyskeratosis Congenita

Answer 13

AD or AR

Question 14

What is the etiology of Dyskeratosis Congenital?

Answer 14

Defect in telomerase

Question 15

3 major features of Dyskeratosis Congenita

Answer 15

Anomalies in pigmentation and fingernails, premature grading, BM failure

Question 16

What is the etiology of Lynch Syndrome?

Answer 16

Defect in DNA mismatch repair

Question 17

What are the mismatch repair genes?

Answer 17

MLH1, MSH2, MSH6, PMS2

Question 18

What is the etiology of MUTYH-associated polyposis?

Answer 18

Defect in base excision repair

Question 19

What is the etiology of Xeroderma Pigmentosa, Cockayne syndrome and Bloom syndrome?

Answer 19

Defect in nucleotide excision repair

Question 20

What are 4 methods for fixing single-stranded DNA mistakes?

Answer 20

DNA polymerase proofreading, mismatch repair genes, base excision repair, nucleotide excision repair

Question 21

What are the 2 mechanisms to fix double-stranded DNA breaks?

Answer 21

End-joining, homologous recombination repair

Question 22

What are the 3 steps of RNA processing?

Answer 22

Capping of 5’ end, splicing to remove introns, cleavage and Poly-A of 3’ end

Question 23

Abnormal splicing is observed in what AR disease that affects lungs, pancreas and reproductive tract?

Answer 23

CF

Question 24

What is the start codon and what aa does it encode?

Answer 24

AUG- met

Question 25

What are the 3 stop codons?

Answer 25

UAA, UAG, UGA

Question 26

What is the ‘etiology’ of the deltaF508 mutation in CFTR

Answer 26

Defect in protein folding

Question 27

What affect does methylation have on gene expression

Answer 27

Decreases

Question 28

DMD is usually due to what type of mutation

Answer 28

Deletion

Question 29

What type of mutation causes Fragile X and HD?

Answer 29

Triplet Repeat