introns only cause variations in individuals .So they are necessary for variations

Introduction

In molecular biology, introns are non-coding sequences found within a gene. Introns are transcribed into RNA along with coding sequences, but they are removed through a process called splicing before the RNA molecule is translated into a protein. The presence of introns and the splicing process have significant implications for evolutionary biology.

Antiquity of Introns

The presence of introns in genes is reminiscent of antiquity because they are found in almost all eukaryotic organisms, from simple unicellular algae to complex mammals. In contrast, prokaryotic organisms, such as bacteria, lack introns. The discovery of introns in the 1970s challenged the long-held assumption that genes were continuous stretches of coding sequences. The presence of introns in eukaryotic genes suggests that introns were present in the last common ancestor of all eukaryotes and that they have been conserved through billions of years of evolution.

Dominance of RNA World

The process of splicing represents the dominance of the RNA world because it is a process that is carried out by RNA molecules. The RNA world hypothesis suggests that the first life forms on Earth were based on RNA, which can both store genetic information and catalyze chemical reactions. Splicing is a complex process that involves the recognition and removal of introns by a complex of RNA molecules called the spliceosome. The spliceosome is made up of small nuclear RNA molecules (snRNAs) that catalyze the splicing reaction. The fact that splicing is carried out by RNA molecules supports the RNA world hypothesis.

Conclusion

In conclusion, the presence of introns in genes and the process of splicing have significant implications for evolutionary biology. The conservation of introns through billions of years of evolution suggests that they are functionally important, and the fact that splicing is carried out by RNA molecules supports the RNA world hypothesis. The study of introns and splicing continues to be an active area of research in molecular biology.