Key points from article :
A database of proteins, the unknome, revealed that we still know next to nothing about thousands of human proteins.
Closely related human genes or proteins were grouped on the basis of similar functions, resulting in around 7500 protein clusters.
Proteins found in commonly studied animals were later added to these clusters, as these probably also have the same function.
Each protein cluster was scored based on entries about its members in its main repository, the Gene Ontology Resource.
Best-studied proteins have scores of well over 100, for example sonic hedgehog scores 168, while p53 scores 126.
Human protein that hasn’t been directly studied still scores highly if an equivalent protein has been well studied in another animal.
Proteins also get higher scores for entries that are regarded as more reliable, such as having been published in a journal.
More than 2200 proteins have scores below 2, 1100 score below 1 and more than 800 score 0.
Low-scored proteins might not have been studied considering they don’t do anything important
Researches tested the importance of these low-scored proteins using a technique called RNA interference (RNAi).
Death occurred in fruit flies after lowering 260 proteins with scores below one, showing the essential function of these protein.
Funding bodies and researchers are reluctant to risk studying unknown proteins in case they turn out not to do anything important.
“They just assume that every possible important gene has been found, which turns out, of course, not to be true,” - Sean Munro, corresponding author.
Study by MRC Laboratory of Molecular Biology, published in PLOS Biology.