Researchers from the University of Cambridge and University College London used a metric based on Gene Ontology biological process terms to determine which budding yeast, fission yeast, and human proteins have been characterized and which have not. As they report in Open Biology, they confirmed previous estimates that about 20 percent of proteins are uncharacterized in each species.
As New Scientist notes, for yeast, the function of most proteins was teased out in the 1990s, but progress on determining the role of the rest declined in the ensuring decades.
When they considered into why these proteins might be tricky to describe, the researchers noted that, for fission yeast, some of these genes weren't essential for growth in rich media. Additionally, they write that even after the sequencing of the human genome, many investigators stuck to studying genes that were described prior to that, likely due to the availability of tools, funding, and career options.
"They must be doing something pretty important," first author Valerie Wood from Cambridge tells New Scientist about the uncharacterized proteins. "I'm absolutely certain there are big discoveries to be made."