Haemoglobinopathies

Question 1

Genes for alpha chain is on

Answer 1

Chromosome 16

Question 2

Gene for beta chain is on

Answer 2

Chromosome 11

Question 3

Types of haemoglobin

Answer 3

Haemoglobin A1
Haemoglobin A2
Fetal haemoglobin

Question 4

What globin gene is expressed at low level in early fetal life

Answer 4

B globin gene

Question 5

Fetal to adult Hb occurs at

Answer 5

3-6 months

Question 6

Regulator of switch to adult haemoglobin is

Answer 6

BCL-11a

Question 7

Normal adult blood contains these haemoglobin a

Answer 7

HA- Alpha and Beta
HA2 - Alpha and Sigma
Hf- Alpha and gamma

Question 8

In sickle cell the RBC becomes sickle shaped when

Answer 8

Subject to low oxygen tension

Question 9

HbS(sickle cell) is caused by

Answer 9

point mutation in the normal gene for Beta globin at position 6 in which adenine is replaced by thymine.(glutamic acid is replaced by valine)

Question 10

Other abnormal genes for Sickle cell are

Answer 10

C,D,E( HbC, HbD, HbE)

Question 11

Deoxygenated HbS tend to - at low oxygen tension

Answer 11

Crystallize our of solution since it is less soluble

Question 12

What causes vasoconstriction in sickle cell

Answer 12

Due to diminished NO

Increased blood viscosity

Question 13

Receptors on red cell that binds

Answer 13

CD36, thrombospodin and intergrin

They bind it fibronectin, VCAM

Question 14

Thalassemia is quantitative

Answer 14

True

Question 15

Inclusion bodies(accumulation of alpha globin chains) formed in the bone marrow is seen in

Answer 15

B thalassemia

Question 16

Cause of anemia in B thalassemia are

Answer 16

Ineffective erythropoietsis

Haemolysis

Question 17

Causes of Anaemia in Alpha thalassemia

Answer 17

Ineffective erythropoietsis
Haemolysis
Low HBA