Question

Chromosome breaks and the two fragments join together but after rotating at ${180}^{\circ }$. The aberration is called as

• A. Translocation
• B. Inversion
• C. Tandem duplication
• D. Reverse tandem duplication

Answer 1

The correct option is B Inversion

Inversion is chromosomal mutation where a segment of a chromosome is reversed end to end. It occurs by introduction of a break in a single chromosome, its rotation by l80${}^o$ followed by its reinsertion in the same location. Rearrangement of the chromosomal segment between two non-homologous chromosomes is called as translocation. Tandem duplication is the presence of extrachromosomal segment which is attached to the normal homologous chromosome causing duplication of a set of genes on the same arm in the same chromosome. Reverse tandem duplication is the presence of extrachromosomal segment causing duplication of a set of genes on the same arm, but in reverse order, in the same chromosome. The correct option is B.