Principles of Inheritance and Variation Question 145
145. An abnormal human baby with ’ $X X X$ ’ sex chromosomes was born due to :
[2015 RS]
(a) formation of abnormal ova in the mother
(b) fusion of two ova and one sperm
(c) fusion of two sperms and one ovum
(d) formation of abnormal sperms in the father
Show Answer
Answer : a
Hints & Solution
(a) A human baby having abnormality with ’ $XXX$ ’ sex chromosomes is born due to evolution of abnormal ova in mother’s ovary. This is caused due to non-disjunction of $X$ chromosome in the mother.
