AN- One biological explanation

Question 1

What did Kipman et al discover the concordance rates in twins were for AN?

Answer 1

MZ- 46.2%
DZ-7.1%

Question 2

What did Woodside et al discover in his family study related to AN?

Answer 2

Found that first degree relatives are more likely to share having anorexia than 3rd degree relatives.
First degree relatives share more genetics than 3rd.

Question 3

What specific genes could be related to anorexia ?

Answer 3

• EPHX2
• ITPR3
• DAT1
  5-HTR2 (seretonin)

Question 4

What role does the EPHX2 gene play?

Answer 4

• This gene produces an enzyme that
helps regulate cholesterol metabolism.
• Cholesterol metabolism is connected
to serotonin, a chemical linked to
anxiety and depression.
• The gene also influences parts of the
brain involved in eating and hunger
(the hypothalamus) and the fear
response (amygdala).

Question 5

What problem does a problem to the EPHX2 gene mean?

Answer 5

Problems with this gene’s expression
may cause fear, and low mood around
food due to its impact on both hunger, regulation and fear response

Question 6

What does the ITPR-3 gene code for?

Answer 6

This gene codes
for a protein
involved in
detecting the taste
of food, such as
bitter and sweet

Question 7

What happens if there is a fault to the ITPR-3 gene?

Answer 7

If this gene is
faulty in those with
AN it could mean
they are unable to
use taste as a
motivator to eat.

Question 8

What does the DAT-1 gene code for?

Answer 8

DAT1 is a specific gene
linked to the function of
dopamine on the reward
system.

Question 9

What happens if there’s a fault to the DAT-1 gene?

Answer 9

• If the gene is mutated
this can mean dopamine
activity is disrupted,
resulting in lack of
motivation and
satisfaction others would
normally get after
eating.

Question 10

What is a weakness of explaining AN solely by a single gene?

Answer 10

No one gene can explain the physical, cognitive and behavioural symptoms of AN.
Oversimplification