Question

To study genetic variations (i.e. mutations) between species, especially highly divergent species like insects and mammals, what type of genetic regions or genes have to be used? Give two examples​

Answer 1

Through the course of evolution all the organisms both living and extinct have evolved with diversifying genetic material. The changes that occur in the genetic code is known as variations/mutations, which are inherited by the off-springs, leading to evolution of different species. Mutation occur at a very high frequency and not all mutations lead to evolution.

The non-coding region of DNA is less prone to mutations. Variable number tandem repeats (VNTRs) and short tandem repeats (STPs) of the satellite regions of the chromosomes contains nucleotide sequence which are conserved from mutations, across different species. These conserved sequences are used to identify genetic relationship between different species of organisms. These sequences remain mostly unchanged (very less variations); their sequence similarities and dissimilarities are analyzed to draw genetic map, which helps to understand evolutionary pattern. This technique is often referred as DNA fingerprinting.

Mitochondrial DNA is also subjected to very few mutations and so, the mitochondrial genome of different species can be matched to verify their evolutionary relationship and the genetic variations between species.