Source: School of Life Sciences
Written by: School of Life Sciences
Edited by: Wang Dongmei

A perspective of Drs Xionglei He and Li Liu from Sun Yat-sen University was published in Science insights section, which has discussed the prospective studies in molecular evolution.

Current studies in molecular evolution are almost entirely retrospective, with a focus on the mutations that were fixed during evolution, and the conclusions are often explanatory, offering no predictive insights. Because only a tiny fraction of all mutations that have ever occurred during evolution have been fixed, the “successes” that we see today provide an incomplete or even biased understanding of the evolutionary process.
 

One way to circumvent this problem is to obtain the whole fitness landscape of a gene to understand, prospectively, chance and necessity in evolution, though it is a huge challenge because of the enormous mutational space. The advent of second-generation DNA sequencing goes some way toward addressing this problem. Two studies in the same issue have characterized the in vivo fitness landscape of two RNA genes. Both studies estimated the relative fitness of >60,000 mutant alleles of each gene.

He and Liu proposed the perspective of prospective studied by fitness landscape. They suggested that fitness landscape can provide a prospective understanding of chance and necessity in evolution, and it provide a new perspective for the researches in molecular evolution, such as evolutionary rate, the evolution from a local fitness peak to the global fitness peak. In addition, it will be very useful in controlling viral epidemics or preventing antibiotic resistance.