Principle Of Inheritance And Variation Question 392
Question: Sickle cell anaemia is:
Options:
A) caused by substitution of valine by glutamic acid in the beta globin chain of haemoglobin.
B) caused by a change in a single base pair of DNA.
C) characterised by elongated sickle-shaped RBCs without a nucleus.
D) an autosomal dominant trait
Show Answer
Answer:
Correct Answer: B
Solution:
Sickle cell anaemia is an autosomal recessive trait that can be transmitted from parents to offspring when both the parents are carriers for the gene (or heterozygous).
It is caused by a change in a single base pair of DNA.
Sickle-cell anaemia is the name of a specific form of sickle-cell disease in which there is homozygosity for the mutation that causes HbS.
Sickle-cell disease, or sickle-cell anaemia, is a life-long blood disorder characterised by red blood cells that assume an abnormal, rigid, sickle shape.
Sickling decreases the cells flexibility and results in a risk of various complications.
BETA
