Question

The letters represent regions of the genome and the asterisk represents the centromere. The un-rearranged (wildtype) chromosomes is:

ABC∗DEFGHIJ
Match each mutant chromosome to the structural change that has occurred to produce it.
1 ABFED∗CGHIJ
2 ABC∗DEDEFGHIJ
3 ABC∗FGHIJ
4 ABC∗DEYZFGHIJ
5 ABC*DEIHGFJ

Answer 1

The student's problem involves matching mutant chromosomes with their corresponding structural changes: a pericentric inversion for Mutant 1, a duplication for Mutant 2, a deletion for Mutant 3, an insertion for Mutant 4, and an inversion for Mutant 5.

Step-by-step explanation:

The question relates to deciphering chromosomal structural rearrangements by comparing a wildtype chromosome sequence with sequences of mutant chromosomes. We use the wildtype configuration ABC*DEFGHIJ as a reference to identify the types of rearrangements that have produced the mutations.

• Mutant chromosome 1 (ABFED*CGHIJ): This rearrangement appears to be a pericentric inversion, where the segment DEF has been inverted to produce FED.
• Mutant chromosome 2 (ABC*DEDEFGHIJ): This rearrangement is a duplication of the DE segment.
• Mutant chromosome 3 (ABC*FGHIJ): This is an example of a deletion where the DE segment has been removed.
• Mutant chromosome 4 (ABC*DEYZFGHIJ): Here, an insertion of new material YZ has occurred within the sequence.
• Mutant chromosome 5 (ABC*DEIHGFJ): This sequence illustrates an inversion where the segment FGHI has been inverted to IHGF.