Ethnicity and Haemoglobinopathies

Question 1

What pattern of inheritance does Sickle cell anaemia have?

Answer 1

Autosomal recessive pattern of inheritance

Question 2

What mutation does Sickle cell anaemia have?

Answer 2

Point mutation, of Glutamic acid to Valine on position 6 of the Beta globin chain, producing HbS instead of Hb

Question 3

What symptoms do HbS carriers have?

Answer 3

Polymerisation problems are minor, because the normal allele can produce >50% of HbA. Carriers only become symptomatic at times of stress (i.e. mountain climbing), and fragility protects against Malaria

Question 4

Does homozygous affected HbS protect against Malaria?

Answer 4

No

Question 5

What is Thalassemia?

Answer 5

A group of haemoglobinopathies characterised by reduced / absent synthesis of globin chains

Question 6

What are the two classes of Thalassemias?

Answer 6

Alpha thalassemia

Beta thalassemia

Question 7

Define “primary prevention”

Answer 7

The prevention of disease or injury before it ever occurs

Question 8

Define “secondary prevention”

Answer 8

Reduction of impact of a disease or injury that has already occurred

Question 9

Define “tertiary prevention”

Answer 9

Softening of impact of an ongoing illness that has lasting effects