GEGE

Question 1

Haplosufficient

Answer 1

When one allele is sufficient to produce a phenotype.

Question 2

Haploinsufficient

Answer 2

When one allele is not sufficient to produce a phenotype –> must be homozygous

Question 3

Loss of Function Mutations

Answer 3

Null/ amorphic mutation

Leaky/ hypomorphic mutation

Question 4

Amorphic mutation

Answer 4

Complete loss of gene function.

Question 5

Hypomorphic mutation

Answer 5

Partial loss of gene function

Question 6

Dominant -ve mutation

Answer 6

Mutation in polypeptide which interferes with a protein’s functioning.

Question 7

Incomplete dominance

Answer 7

Will show a mix of the two phenotypes e.g flower colour

Question 8

Co-dominance

Answer 8

Will should both phenotypes e.g blood type

Question 9

Pleiotrophy

Answer 9

When a single gene affects two or more characteristics.

Question 10

Incomplete Penetrance

Answer 10

Individual with mutant allele may not show the mutant phenotype

Question 11

Variable expressivity

Answer 11

The extent to which the phenotype is expressed varies

Question 12

Complementary Gene Interaction (form of epistasis)

Answer 12

Recessive mutation in two different genes acting in the same pathway produce the same phenotype
Wild type alleles for both genes need to be present for both genes to produce the wild type phenotype.

Question 13

Duplicate Gene Interaction (form of epistasis)

Answer 13

Only homozygous mutation in both genes produce a mutant phenotype

Question 14

Dominant Gene Interaction (form of epistasis)

Answer 14

Two genes contribute to a phenotype
Phenotype 1 = both genes have a dominant allele
Phenotype 2 = either gene is recessive
Phenotype 3 = both gene are recessive

Question 15

Dominant Supression (form of epistasis)

Answer 15

The dominant allele of one gene supresses the phenotypic expression of alleles of a second gene

Question 16

Dominant Epistasis (form of epistasis)

Answer 16

A dominant allele of one gene supresses or masks the phenotypic expression of alleles of a second gene.

Question 17

Recessive Epistasis (form of epistasis)

Answer 17

Homozygous recessive alleles for one gene masks the phenotypic expression of alleles at a second gene.

Question 18

Cell Cycle

Answer 18

Interphase -> Prophase -> Prometaphase -> Metaphase -> Anaphase -> Telophase

Question 19

Interphase

Answer 19

Chromatin condense and transition to polar ends of the cell

Question 20

Prophase

Answer 20

Chromosomes condense and spindles attach

Question 21

Prometaphase

Answer 21

Nuclear membrane dissolves

Question 22

Metaphase

Answer 22

Spindle fibres align chromosomes along equatorial plate

Question 23

Anaphase

Answer 23

Sister chromosomes pulled apart

Question 24

Telophase

Answer 24

Nuclear membrane reforms and cytoplasm begins to divide

Question 25

Metacentric chromosomes

Answer 25

Centromere in middle of chromosome

Question 26

Acrocentric chromosomes

Answer 26

Centromere towards one teleomere

Question 27

Telometric chromosomes

Answer 27

Centromere right at the end of the chromosome

Question 28

Aneuploidy

Answer 28

variation in chromosome dose e.g downs sydndrome

Question 29

Polyploidy

Answer 29

Variation in sets of chromosomes

Question 30

Allopolyploidy

Answer 30

Sets of chromosomes come from different species --> sterile hybrid produced.

Question 31

Haplotypes

Answer 31

A block of genes located together which are inherited together

Question 32

Tautomers

Answer 32

Alternate forms of the nucleotide bases | i.e C+A and T+G

Question 33

Indels

Answer 33

Addition or deletion of bases

Question 34

Transitions

Answer 34

Purine replaced with another purine and a pyrimidine is replaced with another pyrimidine

Question 35

Transversions

Answer 35

Purine replaced with a pyrimidine and a pyrimidine is replaced with apurine

Question 36

Silent Mutation

Answer 36

bp change --> no AA change

Question 37

Missense mutation

Answer 37

bp change --> AA change

Question 38

Non-sense mutation

Answer 38

bp change --> early stop codon

Question 39

Frameshift

Answer 39

bp deletion/addition --> alters reading frame

Question 40

Mutant Screening Strategies

Answer 40

Forward genetic screen Genome-wide screen Reverse genetic screen

Question 41

Forward Genetic Screen

Answer 41

Take organism -> mutate -> look at individual mutants which alter function/development

Question 42

Genome-wide screen

Answer 42

Target all of genes using CRISPR -> get mutations -> identify what gene it is based on the mutation

Question 43

Reverse Genetic Screen

Answer 43

Guess which gene is causing a mutation -> directly target that gene and mutate it -> see if the two mutations are the same.

Question 44

Genetic Variation Comes From?

Answer 44

Mutation Sexual Reproduction Migration

Question 45

Changes in allele frequency due to...

Answer 45

Mutation Migration Selection Inbreeding

Question 46

Inbreeding depression

Answer 46

Decrease in growth, fertility and survival following inbreeding and an increase in homozygosity

Question 47

Hybrid Vigor

Answer 47

increase in vigor often after crossing inbred lines

Question 48

Qualitative Traits

Answer 48

Controlled by a few genes of large effect Phenotype determined by simple crossing experiment E.g eye colour in drosophila

Question 49

Quantitative Traits

Answer 49

Controlled by many gene of small effect Environmental factors contribute to phenotype E.g IQ

Question 50

Structural Genomics

Answer 50

Sequencing and analysis of genome infromation

Question 51

Comparative Genomics

Answer 51

Infer sequence function, understand genome evolution

Question 52

Functional Genomics

Answer 52

What genes do and their link to phenotype

Question 53

Evolutionary Genomics

Answer 53

Identifies similarities/differences between individuals/species

Question 54

Interspecific Comparison

Answer 54

Between members of the same species | Identify sequences conserved over evolutionary time

Question 55

Intraspecific Comparison

Answer 55

Identify sequence polymorphisms responsible for genetic differences between individuals

Question 56

Paralogs

Answer 56

Genes which have originated from the duplication of an ancestral gene -> functions distinct but related

Question 57

Orthologs

Answer 57

Genes in different species derived from a single ancestral gene -> have equivalent functions in different species

Question 58

Phylogenetic footprinting

Answer 58

identify conserved regions in diverse species

Question 59

Phylogenetic shadowing

Answer 59

look at sequences which have been conserved and try to determine why