An article published in the journal “Nature Communications” describes a research that identified a genetic mutation that according to the authors may have contributed to the development of certain organs in various species of vertebrates, including humans. This is a very old mutation, which may have occurred more than 700 million years ago and yet it may have had consequences long after, for example in the development of lungs and inner ear but also in forelimbs.
The gene object of this research belongs to the family of the fibroblast growth factor receptors (FGFRs). The image (©Takuma-sa) shows a molecular representation of a fibroblast growth factor together with one of the receptors, specifically the FGF10-FGFR2b pair. The mutation occurred very early in the course of the evolution of complex organisms, more than 700 million years ago, after the separation from sea anemones (Actiniaria).
Millions of years after that mutation, it caused a link between two groups of regulatory genes, specifically the FGFRs and the ones called Epithelial Splicing Regulatory Proteins (ESRPs). The latter group basically cut and sew genes, in the jargon it performs the splicing, in a way that allows the genome to generate a greater amount of proteins.
This mutation had a number of important long-term consequences on the evolution of many vertebrates and in particular on certain organs and biological structures. The researchers led by Manuel Irimia of the Centre for Genomic Regulation (CRG) in Barcelona studied the functions of ESRP genes during embryogenesis of various animals. The results show that there are common genetic functions among very different species of vertebrates such as fish and human beings that regulate the formation of certain organs and biological structures.
The fact that today in a number of species a group of genes determines those results is strongly influenced by that ancient mutation. The researchers explain that those same genes were used to generate different biological structures and organs during the evolutionary process. Without that mutation, the evolution of those species would have been very different.
Professor Jordi Garcia-Fernàndez of the University of Barcelona, one of the authors of the article, pointed out that a mutated gene was used for many different purposes and this confirms the versatility of biological evolution. A mutation, which is a random event, had a strong long-term impact after a microevolutionary event developed a potential that was selected at macroevolutionary level.