Genetics lecture 6 - quantitative genetics

Question 1

quantitative genetics

Answer 1

how many genes affect a given phenotypic trait , eg skin colour

Question 2

two kinds of variation

Answer 2

discrete and continuous

Question 3

discrete variation

Answer 3

discrete variation is when two or more clearly distinguished alleles are associated with a single locus or gene

Question 4

mendelian disorders

Answer 4

disorders caused by a single gene

Question 5

continuous variation

Answer 5

when the phenotype of a certain gene is expressed along the population in a continuumm. eg height

Question 6

quantitative traits

Answer 6

traits that can be expressed numerically

Question 7

why are quantitative traits also called polygenic traits

Answer 7

because they are caused by multiple genes

Question 8

epistasis

Answer 8

when the expression of a gene is controlled by another gene eg the expression of one gene will affect the expression of another gene.

Question 9

multifactorial genes

Answer 9

traits that depend on multiple genes combined with environmental factors

Question 10

heritability

Answer 10

the likelihood of a single trait being caused by genetic factors

Question 11

brain wiring and genetics

Answer 11

the integrity of the mylein sheath that encasses the nerve cells in the brain have shown to affect how fast chemical signals are transmitted in the brain

Question 12

brain imaging in twins

Answer 12

brain imaging has in twins has been used to show the heritability of certain traits.
the integrity of the myelin sheath in twins , using brain imaging, has been shown to be similar, i.e intelligence may be a heritable trait.

Question 13

SNPs

Answer 13

A single-nucleotide polymorphism (SNP, pronounced snip) is a DNA sequence variation occurring when a single nucleotide adenine (A), thymine (T), cytosine (C), or guanine (G]) in the genome (or other shared sequence) differs between members of a species or paired chromosomes in an individual.

Question 14

GWAS

Answer 14

genome-wide association studies

Question 15

genome editing

Answer 15

cutting genes at specfic gene sequences to either inhibit a gene, or to replace a mutated sequence in a gene

Question 16

Actute lymphoblastic leukemia treated with genome editing

Answer 16

genes are added to healthy donor t cells to arm them against leukemia in two ways.
gene editing is used to make them invisible to a drug against leukemia that usually kills them.
it also reprogrammes them to only target leukemia cells.

Question 17

ladders

Answer 17

a control in which the dna length are known