The Human Genome Project was declared fully complete in 2022. It lists the entire genome for the human body. Genes 'code' for specific protein production within cells. Although many of the important proteins now have very well-cataloged lists of functions, many others are completely obscure. The number of these unknown proteins - many thousands of them - is currently estimated to be around 20% of the total.

Some of them are almost certainly fundamental* to life itself, as they're found in a huge range of organisms - from humans to flies to worms etc. etc. - nevertheless their function is entirely unknown.

A project from the Dunn School of Pathology, University of Oxford, and the MRC Laboratory of Molecular Biology, Cambridge, UK, has recently launched a database of these unknown proteins - which they call the 'Unknome' . The technical database lists proteins according to their degree of 'known-ness'.

For further details of the project, see Functional unknomics: Systematic screening of conserved genes of unknown function PLOS Biology, Aug 2023.

* Note : It's possible that some of these proteins have absolutely no function in humans, and are there simply as 'relics' from 'ancestor' organisms earlier in our evolution.