Question

What are four types of chromosomal mutation?

Answer 1

Hint: Chromosomes are molecules that have packaged DNA molecules. They are found in the nucleus of the cell. The chromosome is the basic unit to establish the heredity of a person as it consists of genes that encode the person’s specific characteristics.

Complete answer:
Alteration in the genome’s nucleotide sequence of an organism, extrachromosomal DNA, or a virus is referred to as a mutation. Mutations occur due to natural occurring errors, DNA replication, evolutionary process, viral replication, meiosis, and mitosis. Chromosomal mutations affect large parts of DNA that consist of various genes. They occur as a result of mistakes in crossing over during meiosis. There are four types of chromosomal mutations.
Duplication: When the sister chromatids are not the replica of each other and are not able to split in the middle due to some redundancy in the genes of that sequence, duplication occurs. These sister chromatids are separated into different cells where they overexpress the traits and produce more proteins.
Deletion: Deletion of a part of a chromosome during meiosis resulting in the break-off in the chromosome and losing the part is deletion. Deletion is a fatal mutation as it can cause the death of the zygote if the sequence lost is vital for survival.
Translocation: When the broken piece of the chromosome is not completely lost but it gets attached to a different, non-homologous chromosome that has also lost a part. This is referred to as translocation. It can cause serious problems due to the genes encoded in the wrong location.
Inversion: a part of a chromosome breaks off and is inverted. It then attaches itself to the same chromosome. This is referred to as inversion. This type of mutation is referred to as a silent mutation.

Note:
DNA is a double helical structure that is densely packed into chromosomes. A special type of protein known as the histone protein tightly packs the DNA into octamers and forms a nucleosome. These nucleosomes are further packed tightly into chromatins. These chromatins are then packed densely to form chromosomes.