Trigger 10: Obesity Genetics

Question 1

BMI=

Answer 1

weight in kg/ height in M2

Question 2

centiles by age and sex are defined to pass through

Answer 2

18.5 BMI at the age of 18 in 6 populations

Question 3

why should doctors be worried about obesity

Answer 3

• Cancer
• T2DM
• CVD
• Blood pressure
• Arthritis
• Mental health

Question 4

BMI is not always part of

Answer 4

some CVD risk calculation methods

Question 5

name a risk calculation for CVD that does not included BMI

Answer 5

framingham risk score of fatal cardiovascular events

Question 6

what does framingham risk score of fatal cardiovascular events take into account

Answer 6

cholesterol, systolic blood pressure, age, sex and smoking status

Question 7

weight and height are highly

Answer 7

polygenic

Question 8

polygenic

Answer 8

traits controlled by two or more genes

Question 9

the obesity epidemic is 100% down to

Answer 9

environment and not genetics

Question 10

why is the obesity epidemic completely related to the environment

Answer 10

we cant change our genetics (at least not at the rate at which he obesity epidemics arisen), but we can change the environemnt

Question 11

example of ways the government has tried to change the environment

Answer 11

sugar tax

Question 12

sugar tax is predicted to prevent how many cases of child obesity per year

Answer 12

95,000

Question 13

poverty and poorer education are

Answer 13

markers of higher obesity

Question 14

well educated and poor educated people

Answer 14

but on weight as they age at the same rate as those from deprived background (e.g. same BMI change per year)

Question 15

what have been found not to work

Answer 15

anti-obesity programmes

Question 16

one anti-obesity programs involved

Answer 16

54 birmingham schools

Question 17

how many children involved

Answer 17

1467 year 1 pupils

Question 18

how long was the intervention

Answer 18

12 moths

Question 19

what did the intervention involve

Answer 19

30 mins a day extra activity

Question 20

findings

Answer 20

no difference between BMI at 15 and 30 months

Question 21

there is also evidence that..

Answer 21

education based intervention in children don’t change BMI (meta-analyses have shown- think of forest plot)

Question 22

what causes obesity

Answer 22

increased obesity and T2DM in the 20-21st century cannot be due to changing genes- must be to do with environment

Question 23

example of people affected by obesity

Answer 23

the Pima indians

Question 24

the Pima indians

Answer 24

used to be a slim race, but now have a high prevalence and incidence of obesity
–> hypothesised to be caused by a change in environment

Question 25

BMI is

Answer 25

heritable- more so than the public perception

Question 26

what can be used to look at the heritability of BMI

Answer 26

twin, family and adoption studies

Question 27

what have twin, family and adoption studies shown

Answer 27

that 50% of variation in BMI is due to eugenic variation

Question 28

dizygotic twins

Answer 28

differences in genetics is evident in differences in height

Question 29

monozygotic twins

Answer 29

similarity of genetics is evident in similarity of height

Question 30

the strength of the genetic component to BMI

Answer 30

is not getting smaller in todays environmental

Question 31

bell curves of identical twins

Answer 31

closely overlapping (nearly on top of each other)

Question 32

bell curves of non-identical twins

Answer 32

only slightly overlapping- like two mountains

Question 33

distant relatedness is correlated with

Answer 33

BMI- suggests that 30% of variation in BMI genetic

Question 34

BMI correlations and genomic relationship matrix show that

Answer 34

those with higher BMI correlations, also have stronger genomic relationships

Question 35

siblings who share 60% of their genome are more similar in BMI than siblings sharing

Answer 35

40 of their genome

Question 36

therefore the more genome that is shared

Answer 36

the more similar BMI

Question 37

most common diseases are caused by

Answer 37

rare single gene forms (SNVs)

Question 38

Name some diseases caused by monogenic mutations

Answer 38

- diabetes - alzheimers - breast cancer - obesity

Question 39

types of monogenic diabetes

Answer 39

neonatal MODY

Question 40

mutations associated with maturity onset diabetes

Answer 40

- HNF1a - HNF1b - HNF2b - Glucokinase

Question 41

mutations associated with neonatal diabetes

Answer 41

- KCNJ11 | - ABCC1

Question 42

alzheimers caused by mutations in what genes

Answer 42

PSEN1

Question 43

breast cancer caused by mutations in what genes

Answer 43

BrCa1/2

Question 44

obesity caused by mutations in what genes

Answer 44

MC4R Leptin

Question 45

name a disease related to mutations in leptin and MC4R

Answer 45

Prader Willi syndrome