Biomarkers- Genetics

Question 1

Definition of a gene

Answer 1

Region of DNA that contains all of the information required to produce a functional protein or RNA

Question 2

Definition of gene locus

Answer 2

The unique position of a gene on the chromosome

Question 3

Definition of genome

Answer 3

All the genetic material (DNA) of an organism

Question 4

Definition of genotype

Answer 4

The genetic constitution of a genome or individual locus

Question 5

Definition of phenotype

Answer 5

The expressed features of the genome as a result of the interaction between the genotype and environment

Question 6

Definition of genetics

Answer 6

The study of single genes and their effects

Question 7

Definition of genomics

Answer 7

The study of all the genes in the genome how they interact and their interactions with environmental factors

Question 8

Definition of epigenetics

Answer 8

The study of reversible, heritable mechanisms that influence gene expression without changing the DNA sequence

Question 9

Definition of wildtype

Answer 9

The most common form of the gene within a population

Question 10

Definition of allele

Answer 10

Alternative form (version) of a gene which has one or more differences in its nucleotide sequence

Question 11

Definition of biallelic

Answer 11

Genes have two alleles

Question 12

Definition of polyallelic

Answer 12

Genes have multiple alleles

Question 13

Definition of homozygous

Answer 13

When copies of the gene (alleles) on each pair of a homologous chromosome are identical

Question 14

Definition of heterozygous

Answer 14

When copies of a gene (alleles) on each pair of homologous chromosomes are different

Question 15

What is co-dominance in blood groups

Answer 15

When both A and B are expressed because they are dominant

Question 16

What enzyme is A blood

Answer 16

Transferase A

Question 17

What enzyme is B blood

Answer 17

Transferase eB

Question 18

What enzyme is O blood

Answer 18

Inactive transferase

Question 19

What blood can AB blood types receive

Answer 19

A, B and O

Question 20

Who can receive O blood

Answer 20

Anyone

Question 21

What is incomplete dominance

Answer 21

When both alleles are expressed but one allele has more effect than the other
eg. T = straight hair and t = curly hair
Tt= wavy hair

Question 22

What is polymorphism

Answer 22

A difference in DNA of equal or greater to 1% in a population

Question 23

Definition of mutation

Answer 23

A difference in DNA that is associated with disease

Question 24

Definition of haplotype

Answer 24

A set of DNA variations or group of alleles that are inherited together

Question 25

What are germline cells

Answer 25

Cells that contain and transmit genetic information from generation to generation

Question 26

What are somatic cells

Answer 26

All cells other than germline cells

Question 27

Why are offspring genetically different from parents in humans

Answer 27

Independent assortment of homologous pairs of chromosomes during meiosis

Question 27

Why are offspring genetically different from parents

Answer 27

1. Independent assortment of homologous pairs of chromosomes during meiosis 2. Random fertilisation

Question 28

How does crossing over allow for genetic difference

Answer 28

Homologous chromosomes exchange information by recombination during meiosis

Question 29

How does damaged chromosome ends lead to genetic variation

Answer 29

Causes chromosomes to fuse and incorrect separation during meiosis Leads to gene amplification and loss

Question 30

What are variations in DNA caused by

Answer 30

Errors in DNA replication Damage to DNA caused by the environment

Question 31

When are variations in DNA maintained in the germline DNA

Answer 31

They are not harmful Provide an advantage

Question 32

How do variations have a phenotypic effect

Answer 32

They must occur in the regulatory or coding region of a gene

Question 33

How do variations effect the regulatory region of a gene

Answer 33

Altered efficiency of: Transcription Translation Splicing

Question 34

How do variations effect the coding region of a gene

Answer 34

1. Alter the amino acid sequence of a protein and its function 2. Affect the rate of folding of the protein 3. Have an affect on protein stability

Question 35

What are the 5 types of genetic variation

Answer 35

1. Single nucleotide polymorphism 2. Base deletion or insertion 3. Microsatellites 4. Minisatellites 5. Copy number variations

Question 36

What causes single nucleotide polymorphism

Answer 36

Base substitution in 1 in every 1000 bp

Question 37

What is a synonymous SNP

Answer 37

No change to the amino sequence

Question 38

What is a non synonymous- conservative missense SNP

Answer 38

Conservative change in the amino acid sequence because the side chains of bases are similar

Question 39

What is a non synonymous- nonconservative missense SNP

Answer 39

Nonconservative change in the amino acid sequence because side chains of bases are different

Question 40

What is a non synonymous- nonsense SNP

Answer 40

Change in the bases that encodes for a stop codon

Question 41

What is another word for base insertion or deletion

Answer 41

Indels

Question 42

How does base insertion occur

Answer 42

When strand slippage occurs in newly synthesised DNA, a base is inserted