Humans Have Kept Evolving New Genes

Researchers at Trinity College Dublin have found two new human-specific ‘microgenes’ that arose from scratch.

FREMONT, CA: According to recent findings, contemporary humans have been evolving ever since they diverged from chimpanzee ancestors almost 7 million years ago.

To compare humans to other vertebrate species, the researchers at Trinity College Dublin looked at a previously released dataset of functionally relevant novel genes and built an evolutionary tree. The researchers found 155 DNA sequences that appeared to be de novo or to have originated from scratch rather than through duplication, by following the relationships between these genes throughout evolution. Two of these novel microgenres are unique to humans.

Three of these 155 genes have disease-associated DNA markers that suggest associations with Alazami syndrome, retinitis pigmentosa, and muscular dystrophy.

The scientists also discovered a brand-new gene linked to human heart tissue, which they think first appeared in humans and chimpanzees after they diverged from gorillas. This demonstrates how quickly a body-essential gene can develop. Professor Aoife McLysaght of Trinity College Dublin and Nikolaos Vakirlis from the Alexander Fleming Biomedical Sciences Research Center in Greece carried out the study.

Understanding what these microgeneses might accomplish and whether they might be directly engaged in any form of disease would be highly fascinating in future studies. Researchers became interested in gene evolution and figuring out how these genes originate in 2017, which is why they started researching these new genes.

It was put on hold for a while until another study with some intriguing data was published, which allowed us to begin this work. Since it is challenging to directly test human-specific genes, the study team looked at DNA patterning that could provide clues about the functions of the genes. Geneticist McLysaght noted that despite the challenges of this study, it was very exciting to be working on something so novel.

It's hard to know if it is biologically meaningful when you start going into these small amounts of DNA. They're really on the border of what is interpretable from a genome sequence. These genes are easy to overlook since they are challenging to examine, but it will become more and more clear that they need to be looked at and taken into account. If the assumptions are correct, the human genome likely contains a lot more functionally useful information.