Question

Which of the following statements is not correct
for sickle cell anaemia?
(a) Sixth amino acid (from NH₂ terminal) of
β chain is glutamic acid
(b) Erythrocytes elongates and form sickle
shaped cells
(c) Individual homozygous haemoglobin
S allele HBβˢ /Hbβˢ
(d) β chain of haemoglobin S contains valine.

Answer 1

Answer:

c is the correct answer

Answer 2

The incorrect statement regarding the sickle cells is (b) Erythrocytes elongates and form sickle  shaped cells.

• Sickle cell anaemia is a genetic disorder in which Valine is replaced in the beta haemoglobin chain instead of Glutamic Acid.
• This alteration contributes to the shift in RBC's form from disk to sickle-like shape leading to reduced oxygen in the body.
• People with this disorder have a normal hemoglobin molecules called hemoglobin S, which may turn the red blood cells into a sickle or crescent form.
• The gene defect is a recognized mutation of the -globin gene from a single nucleotide (A to T), resulting in glutamic acid being substituted by valine at position 6.