Organization of the Human Genome

Question 1

Rett Syndrome

Answer 1

Caused by loss-of-function mutations in MECP2 and results in aberrant activated overexpression of neuronal genes to cause severely debilitating neurologic symptoms.

Question 2

Quinolones

Answer 2

Floxacin drugs. Antibiotics are used in the treatment of urinary tract infections. Targets bacterial DNA gyrase (type II topoisomerase)

Question 3

Etoposide and Teniposide

Answer 3

Anti-cancer agent used to treat several neoplastic diseases. Anti-cancer agent used to treat childhood cancers and Hodgkin’s lymphoma.

Question 4

Doxorubicin and Daunorubicin

Answer 4

Anti-cancer agent used to treat acute lymphatic and acute myeloid leukemias. Interacts with DNA and inhibits progression of type II topoisomerase

Question 5

Nonsense (STOP)

Answer 5

Mutations cause the premature termination of a protein during translation

Question 6

Missense

Answer 6

Mutations cause the incorporation of the wrong amino acid into a protein

Question 7

Frame-shift

Answer 7

Mutations cause a change in a protein’s reading frame during translation

Question 8

Splicing Mutations

Answer 8

cause abnormal skipping or retention of exons during transcription

Question 9

Indels

Answer 9

Within a protein-coding sequence causes frameshift mutations unless changes result in a net change that is a multiple of three

Question 10

Sickle Cell Anemia

Answer 10

SCA is a missense mutation due to a single nucleotide substitution in an exon of B-globin gene DNA sequence

Question 11

Cystic Fibrosis

Answer 11

No single mutation is responsible for all cystic fibrosis cases. Single point mutations, small deletions and insertions are all found in the CF gene (CFTR)

Question 12

Mismatch Repair

Answer 12

DNA Polymerase error. Deals with correcting mismatches of normal bases that is a failure to maintain normal Watson-Crick base pairing
(A-T and G-C). Recognition of mismatch by several proteins including those encoded by MSH2 and MLH1.

Question 13

Base Excision Repair

Answer 13

Spontaneous depurination. Nucleotide bases can be lost spontaneously. Cytosine undergoes deamination to uracil. Base excision repair involves removal of nucleotides that have lost their base due to depurination.

Question 14

Nucleotide Excision Repair

Answer 14

Environmental damage. UV light is non-ionizing and cannot penetrate beyond the outer layer of the skin but it can form pyrimidine-pyrimidine dimers from adjacent pyrimidine bases in DNA. Causes sunburns and skin cancer

Question 15

Xeroderma Pigmentosun (XP)

Answer 15

A genetic disorder that causes affected individuals to lose the ability to remove UV-induced damage from DNA

Question 16

Double-Stranded Break Repair

Answer 16

Environmental damage. Double strand breaks are repaired by two different types of mechanisms. Homologous recombination (less error-prone, no loss of DNA). BRCA1 and BRCA2 are associated with various cancer types. Non-homologous end-joining. (Error-prone and loss of DNA)

Question 17

Fluorescent in situ hybridization

Answer 17

big chrom abnormalities (chrom translocation, break)

Question 18

Sanger DNA sequencing

Answer 18

known history and gene mutation, specific set of genes

Question 19

qPCR using reverse transcribed DNA as template

Answer 19

RNA sample => reverse transcriptase into DNA, specific set of genes

Question 20

Genotyping with SNPs associated with drug metabolism

Answer 20

UNKNOWN, small nucleotide polymorphisms /w fam history, unsure of gene, looking for markers in family with SNPs