The gene sequence of a chromosome is HIJKL.MNOPQ .
What chromosome change resulted in the following sequences of the
chromosome?
(a) HIJKNM.LOPQ
(b) HIJKL.MNONOPQ
(c) HIJKLLK.MNOPQ
(d) HIJKL.MNCDEFG
Answers
Ans.
Change in chromosome sequence are known as chromosomal rearrangement or chromosomal mutations. There are different ways, by which chromosomal rearrangement occurs, which include insertion, deletion, translocation, and inversion.
Option (a) represents translocation that involves rearrangement between chromosomal parts. In this sequence, HIJK remains unchanged, while there is a translocation between L and MN segments.
Option (b) represents duplication as NO segment gets duplicated in resulting chromosomal sequence.
Option (c) represents inverted duplication. In this sequence, the KL segment was first duplicated and then inverted as LK.
Option (d) represents in translocation or rearrangement, between two different chromosomes as OPQ segment given chromosome was replaced by CDEFG segment of another chromosome.