Principles of Inheritance and Variation Question 155
155. Represented below is the inheritance pattern of a certain type of traits in humans.
Which one of the following conditions could be an example of this pattern?
[2012M]
(a) Thalassemia
(b) Haemophilia
(c) Phenylketonuria
(d) Sickle cell anaemia
Show Answer
Answer : b
Hints & Solution
(b) The inheritance pattern of a particular trait shown in the picture results in haemophilia. Haemophilia is a group of inherited blood disorders in which the blood does not clot properly. It is caused by a fault in one of the genes that determine how the body makes blood clotting factor VIII or IX. These genes are located on the $X$ chromosome.
