1: Introduction to the human genome

Question 1

Genes and the ___ combine to create disease.

Answer 1

environment

Question 2

Strands of DNA pair up in a (parallel / antiparallel) fashion.

Answer 2

antiparallel

Question 3

DNA is read…

a) 3’ to 5’
b) 5’ to 3’

Answer 3

b) 5’ to 3’

Question 4

What is the sugar backbone of DNA called?

Answer 4

2-deoxyribose

Question 5

What is the sugar backbone of RNA called?

Answer 5

Ribose sugar

Question 6

What are the four bases of DNA?

Answer 6

ACGT

Question 7

What are the four bases of RNA?

Answer 7

ACGU

Question 8

The information in DNA is found in the ___ of base pairs.

Answer 8

sequence

Question 9

What are the base pairs of DNA?

Answer 9

A ⇔ T

C ⇔ G

Question 10

What are DNA strands wound into?

Which protein is involved?

Answer 10

Chromosomes

Histone

Question 11

How many bases are found in the human genome?

Answer 11

3 billion

Question 12

How many genes are found in the human genome?

Answer 12

30,000

Question 13

In which phase of the cell cycle does DNA replication occur?

Answer 13

S phase

Question 14

What occurs during the S phase of the cell cycle?

Answer 14

DNA replication

Question 15

___ mechanisms fix DNA damage which may occur during the S phase.

Answer 15

Repair

Question 16

Defects in DNA repair mechanisms can lead to ___.

Answer 16

disease

Question 17

What is cell division otherwise known as?

Answer 17

Mitosis

Question 18

What occurs during mitosis in terms of cell number?

Are the daughter cell(s) haploid or diploid?

Answer 18

One diploid parent cell divides into two genetically identical diploid daughter cells

Question 19

What occurs during meiosis in terms of cell number and ploidy number?

Answer 19

1 diploid parent cell becomes 4 haploid daughter cells

Question 20

Which process introduces variation during meiosis by swapping genes between chromosomes?

Answer 20

Crossing over

Question 21

Meiosis is the process behind ___ formation.

Answer 21

gamete

Question 22

In terms of strand number, what is the difference between DNA and RNA?

Answer 22

DNA is double stranded

RNA is single stranded

Question 23

DNA is ___ into pre-mRNA.

Pre-mRNA is ___ into mRNA.

mRNA is ___ into protein.

Answer 23

transcribed

spliced

translated

Question 24

DNA is transcribed into ___.

Answer 24

pre-mRNA

Question 25

Pre-mRNA is spliced into ___.

Answer 25

mRNA

Question 26

mRNA is translated into ___.

Answer 26

protein

Question 27

How many bases correspond to one amino acid (or a stop)?

Answer 27

3

Question 28

Every copy of the human genome is ___.

Answer 28

different

Question 29

What is a polymorphism?

Answer 29

Any variation in the human genome which appears in > 1% of the population.

Question 30

What are the two components of a karyotype (e.g 46 XX)?

Answer 30

46 - the total number of chromosomes

XX - the sex chromosome complement

Question 31

(Balanced / unbalanced) chromosome rearrangements are liable to cause disease.

Answer 31

Unbalanced

Question 32

What is aneuploidy?

Answer 32

Having a whole extra or missing chromosome

Question 33

What is a Robertsonian translocation?

Answer 33

When two acrocentric chromosomes become stuck end to end.

Question 34

What is the more genetic name for Down Syndrome?

Answer 34

Trisomy 21

Question 35

A Robertsonian translocation is likely to cause ___ - the cause of genetic disorders such as Down Syndrome.

Answer 35

trisomy

Question 36

Why is X chromosome aneuploidy (having one missing or one extra chromosome) better tolerated?

Answer 36

Random X inactivation

Question 37

What genetic disorder has the karyotype 45 X?

Answer 37

Turner syndrome

Question 38

What genetic disorder has the karyotype 47 XXY?

Answer 38

Klinefelter syndrome

Question 39

Other than Robertsonian, name a type of translocation.

Answer 39

Reciprocal translocation

Question 40

Most reciprocal translocations tend to be (balanced / unbalanced);

Answer 40

balanced

Question 41

What does FISH stand for?

Answer 41

Fluoresence in situ Hybridisation

Question 42

FISH allows you to detect individual ___ in genes using fluorescent probes.

Answer 42

mutations

Question 43

Which genetic test can be used to examine a whole genome?

Answer 43

Microarray CGH

Question 44

What are some consequences of unbalanced translocations in developing foetuses?

Answer 44

Malformations

Miscarriage

Question 45

Different cells have different genetic make-ups and will proliferate in a patchy nature - what is this phenomenon called?

Answer 45

Mosaicism

Question 46

Somatic mosaicism for a chromosome abnormality is a genetic change which can contribute towards ___.

Answer 46

cancer

Question 47

Amplification of the HER2 gene is associated with which disease?

How can it be treated?

Answer 47

Breast cancer

HER2+ breast cancer can be treated using HERCEPTIN (trastuzumab), a monoclonal antibody which targets it specifically

Question 48

An abnormality in chromosome 22 (Philadelphia chromosome) can cause which disease?

How can it be treated?

Answer 48

Acute myeloid leukaemia

AML can be treated using IMATINIB, a monoclonal antibody which targets cells which express BCR-ABL, the protein produced as a result of a Philadelphia chromosome translocation