BGM1004/L13 Inheritance II

Question 1

Give the equation for phenotype frequencies for a population in Hardy-Weinberg equilibrium.

Answer 1

P + Q = 1

Question 2

Give the equation for genotype frequencies for a population in Hardy-Weinberg equilibrium.

Answer 2

p^2 + 2pq + q^2 = 1

Question 3

Give 3 conditions in which Hardy-Weinberg equilibrium does not apply.

Answer 3

Gene flow
Genetic drift
Non-random mating
Natural selection

Question 4

What is a Hardy-Weinberg equilibrium?

Answer 4

A population with random mating under no selective pressure

Question 5

What is albinism?

Answer 5

Lack of melanin pigment

Question 6

What is phenylketonuria?

Answer 6

Inability to metabolise phenylalanine

Question 7

What is Tay-Sachs?

Answer 7

Neurodegeneration due to lack of N-acetyl-hexoaminidase

Question 8

What is cystic fibrosis?

Answer 8

Thick mucus due to lack of CTFR

Question 9

What is sickle cell anemia?

Answer 9

Mutation in beta-chain of haemoglobin

Question 10

What is haemochromatosis?

Answer 10

Mutation in HFE gene causing build-up of iron in body

Question 11

Name 3 human autosomal recessive conditions.

Answer 11

Albinism
Phenylketonuria
Tay-Sachs
Cystic Fibrosis
Sickle-cell anemia
Haemochomatosis

Question 12

What is Huntington’s Disease?

Answer 12

Progressive brain disease

Question 13

What is polycystic kidney disease?

Answer 13

Development of cyst clusters primarily in kidneys

Question 14

What is achondroplastic dwarfism?

Answer 14

Failure to convert cartilage to bone
Mutation in FGFR3

Question 15

What is polydactyly?

Answer 15

Extra digits

Question 16

What is hypercholestrolemia?

Answer 16

Missing protein that removes cholestrol from blood
Causes heart attacks by 50

Question 17

What is FASPS?

Answer 17

Familial advanced sleep phase syndrome
Disturbed circadian rhythm

Question 18

Give 3 human autosomal dominant conditions.

Answer 18

Huntington’s
Polycystic kidney disease
Achondroplastic dwarfism
Polydactyly
Hypercholestrolemia
FASPS

Question 19

Where do autosomal recessive diseases reappear?

Answer 19

Progeny of unaffected parents (carriers)

Question 20

How many genes does an X chromosome carry?

Answer 20

900-1400

Question 21

How many genes does a Y chromosome carry?

Answer 21

70-400

Question 22

Name 2 X-linked recessive disorders in humans.

Answer 22

Haemophilia
Duchene & Becker muscular dystrophies
Fragile-X syndrome
Deuteranopia

Question 23

What is retinitis pigmentosa?

Answer 23

Progressive loss of vision leading to blindness
Y-linked disorder

Question 24

What is Leri-Weill dyschondrosteosis?

Answer 24

Pseudoautosomal dominant disorder
Abnormal shortening of forearms and lower legs

Question 25

What causes calico coat colour in cats?

Answer 25

X inactivation