EPIGENETICS

Question 1

what is epigenetics

Answer 1

it is the study of heritable changes- not
caused by changes to the DNA sequence.

when gene expression is altered without changing DNA
structure

Question 2

what is gene expression

Answer 2

only certain genes are transcribed in each cell.
Genes may be turned ‘on’ or ‘off’ depending on the cell and activity. Chemical reactions make this happen.

protein synthesis occurs (on) or doesnt (off)

Question 3

what can be inherited by your offspring?

Answer 3

Environmental factors can cause epigenetic factors

or things you do in your life time

Question 4

3 types of histone modification

Answer 4

1. DNA acetylation
2. DNA deacetylation
3. DNA methylation

Question 5

DNA acetylation

Answer 5

is the addition of an acetyl group to a histone tail. This causes the DNA to relax
and the ability to be read/ copied.

This allows transcription to occur and genes are expressed.

It “switches the gene on’ enhancing gene expression.

Question 6

DNA deacetylation

Answer 6

an enzyme removes the acetyl group from the histone tail. This causes DNA to coil so the DNA cannot be read.

• This restricts transcription (cannot occur). Gene expression is “switched off “

Question 7

DNA methylation

Answer 7

*It is the addition of a methyl group to DNA molecule (base)

• This stops the gene from being read -‘inhibits gene expression’

DA chemical cap to part oR a DNA molecule so it cant be read.

Question 8

can DNA methylation be an issue

Answer 8

If it caps specific, desired genes, like tumor supressor
genes, it can cause issues.

Question 9

influencing factors of gene expression

Answer 9

Chemicals from the environment can impact our epigenome therefore altering gene expression.

Question 10

DNA methylation in inheritance

Answer 10

Methyl groups can stay attached to DNA as they are passed to an offspring through egg/sperm.