Genetic risk calculation (X-linked and dominant)

Question 1

autosomal dominant inheritance

Answer 1

50% risk in offspring
Males and females equally affected
Affected individuals should have an affected parent
Tends to occur in every generation

Question 2

example of autosomal dominant

Answer 2

familial hypercolesterolaemia - raised cholesterol - premature coronary heart disease - mutation of LDL receptor or APOB

huntingtons - - 35-55 and movement cognitive and psychiatric

Question 3

x linked recessive inheritance

Answer 3

No male-to-male transmission
males affected almost exclusively
the gene alteration can be transmitted from female carriers to sons

e.g. haemophilia A and B and DMD

Question 4

x linked dominant

Answer 4

X-linked dominant traits do not necessarily affect males more than females (unlike X-linked recessive traits).

Question 5

Autosomal Recessive

Answer 5

Males and females affected in equal proportions
Affected individuals usually in only a single generation
Parents can be related (i.e., consanguineous)

Question 6

Y-Linked Inheritance

Answer 6

Affected males only

Affected males must transmit it to their sons

Question 7

dominant pedigree analyses

Answer 7

To show not assume it is first to prove- then crete affected on non affected genes and work out generations- with xlinked men will have to show it

Autosomal dominant

create the trees

Question 8

Recessive analysis of sex linked recessive traits

Answer 8

Again start with wrogns so autosomal dominant, recessive and then work out which sex linked
Sex llinked recessive not autosomal recessive as showna bove

Question 9

if penetrance is 100% all will carry the defected gene and will at some point get the disease

Answer 9

e.g. if disease penetrance is 40% and probs of individual is at 50% so risk of AD disorder so 0.5 x 40% =20 %

Question 10

a and B are codomiantn true or false

Answer 10

true