Question

What is chromosomal aberration? Give any two types of aberrations found in the population.

Answer 1

• Definition: The structural and morphological change in chromosomes due to rearrangement is called chromosomal aberrations. It changes the gene arrangement (order or sequence) that results in the variation. Chromosomal aberrations occur due to the following reasons:

1. Deletion: Loss of genes from chromosome.
2. Duplication: Genes are repeated or doubled in number on chromosomes.
3. Inversion: A particular segment of the chromosome is broken and gets reattached to the same chromosome in an inverted position due to 1800 twist. There is no loss or gain of the gene complement of the chromosome.
4. Translocation: Transfer (transposition) of a part of a chromosome or a set of genes to a non-homologous chromosome is called translocation. It is affected naturally by the transposons present in the cell.