Multifactorial Inheritance

Question 1

What is a Multifactorial Condition?

Answer 1

Diseases that are due to a combination of genetic and environmental factors

Question 2

Method to identify that a condition has a genetic component? (3)

Answer 2

Clinical Observation

1) Family Study 2) Twin Study 3) Adoption Study

Question 3

What is the proband?

Answer 3

First person in a family to gain a given illness

Question 4

Risk level trend for an illness in a family?

Answer 4

First degree relatives e.g. Siblings most at risk

Question 5

What is a monozygotic twin and this results in? (vs Dizygotic)

Answer 5

Identical twin so Identical GM and share similar environmental exposure
(Dizygotic Non-id so only half GM)

Question 6

What is the concordance rate?

Answer 6

Rate used to give a rough figure for hereditability of MF condition

Question 7

What is hereditability?

Answer 7

Proportion of aetiology given to GF vs EF

Question 8

Conditions in one particular sex trend?

Answer 8

If 1 sex more common for condition, then relatives of opposite more at risk

Question 9

What is the Liability model?

Answer 9

Factors that influence disease as liability, that form a continuous variable with normal distribution (See curve)

Question 10

How is the curve affected with families?

Answer 10

The greater the relation, the further to the right

Question 11

What is an GWAS?

Answer 11

Shows that gene can have several variants:

1) Some Pathogenic (Inactivated)
2) Polymorphic (still function)

Question 12

How do GWAS work?

Answer 12

Compare frequency of markers in sample of patients and controls (Markers more frequent (SNP)

Question 13

Which environmental agents act on embryogenesis? (4)

Answer 13

1) Drugs/Chemicals
2) Maternal Infections
3) Physical e.g. radiation
4) Maternal Illness