Single Gene Disorders

Question 1

What are single gene disorders caused by?

Answer 1

Point mutations

Question 2

What are autosomal chromosomes?

Answer 2

All chromosomes apart from X and Y

Question 3

Is cystic fibrosis i) autosomal or sex linked ii) recessive or dominant?

Answer 3

Autosomal recessive

Question 4

What is cystic fibrosis?

Answer 4

A disorder originating in secretory epithelial tissue

Question 5

What are symptoms of cystic fibrosis?

Answer 5

Mucus in lungs, pancreas and other organs
Chronic bronchitis
Bacterial infections

Question 6

What gene is affected to cause cystic fibrosis?

Answer 6

CF gene, regulates flow of chorine ions

F508 is the mutation causing CFTR

Question 7

What is treatment of cystic fibrosis?

Answer 7

Antibiotics and massage to clear mucus

Question 8

Is sickle cell anaemia i) autosomal or sex linked ii) recessive or dominant?

Answer 8

Autosomal recessive

Question 9

What are symptoms of sickle cell anaemia?

Answer 9

Anaemia
Dysfunctional RBC
Joint pain
Swollen spleen
Severe infections

Question 10

What are treatments of sickle cell anaemia?

Answer 10

Regular blood transfusion

Question 11

What is a cure for sickle cell anaemia?

Answer 11

Bone marrow transplant

Question 12

What is the cause of sickle cell anaemia?

Answer 12

Mutation in the gene for B-chain of haemoglobin so incorrect folding of protein

Question 13

Who is sickle cell carriers advantageuos for?

Answer 13

People in areas of malaria as it confers resistance to malaria (heterozygote advantage)

Question 14

Is huntington’s disease i) autosomal or sex linked ii) recessive or dominant?

Answer 14

Autosomal dominant

Question 15

What are symptoms of huntingtons disease?

Answer 15

Jerky movement
Personality changes
Deterioration of walking

Question 16

Why is huntings disease still around?

Answer 16

It is a late onset so they have children before they know they have huntingtons?

Question 17

What causes huntingtons disease?

Answer 17

35-125 repeats of CAG in HD gene

Question 18

Is familial hypercholesterolaemia i) autosomal or sex linked ii) recessive or dominant?

Answer 18

Autosomal dominant (incomplete dominance)

Question 19

What are symptoms of familial hypercholesterolaemia?

Answer 19

High cholesterol levels
Cholesterol build up in joints
Cardiovascular disease

Question 20

What is treatment for familial hypercholesterolaemia?

Answer 20

Cholesterol lowering drugs

Low cholesterol diet

Question 21

What causes familial hypercholesterolaemia?

Answer 21

Due to a lack of low density lipoprotein receptor

Question 22

What are sex linked conditions caused by?

Answer 22

Gene on the X chromosome

Question 23

Is haemophilia i) autosomal or sex linked ii) recessive or dominant?

Answer 23

Sex linked recessive

Question 24

What are symptoms of haemophilia?

Answer 24

Bruising
Uncontrolled bleeding
Bleeding into joints

Question 25

What is treatment for haemophilia?

Answer 25

Intravenous injections with the missing protein

Question 26

What are the two types of haemophilia?

Answer 26

A and B

Question 27

What is haemophilia A caused by?

Answer 27

Mutation in the gene for factor VIII on X chromosome

Question 28

What is haemophilia B caused by?

Answer 28

Mutation in gene for factor IX on X chromosome

Question 29

Is duchenne muscular dystrophy i) autosomal or sex linked ii) recessive or dominant?

Answer 29

Sex linked recessive

Question 30

What are symptoms of duchenne muscular dystrophy?

Answer 30

Muscle wasting

Question 31

What casues duchenne muscular dystrophy?

Answer 31

Affected gene codes for a muscle protein called dystrophin