Non-canonical (i.e., unannotated) open reading frames (ncORFs) have until recently been omitted from reference genome annotations, despite evidence of their translation, limiting their incorporation into biomedical research. To address this, in 2022, we initiated the TransCODE consortium and built the first community-driven consensus catalog of human ncORFs, which was openly distributed to the research community via Ensembl-GENCODE. While this catalog represented a starting point for reference ncORF annotation, major technical and scientific issues remained. In particular, this initial catalogue had no standardized framework to judge the evidence of translation for individual ncORFs. Here, we present an expanded and refined catalog of the human reference annotation of ncORFs. By incorporating more datasets and by lifting constraints on ORF length and start-codon, we define a comprehensive set of 28,359 ncORFs that is nearly four times the size of the previous catalog. Furthermore, to aid users who wish to work with ncORFs with the strongest and most reproducible signals of translation, we utilized a data-driven framework (i.e. translation signature scores) to assess the accumulated evidence for any individual ncORF. Using this approach, we derive a subset of 7,888 ncORFs with translation evidence on par with canonical protein-coding genes, which we refer to as the Primary set. This set can serve as a reliable reference for downstream analyses and validation, with a particular emphasis on high quality. Overall, this update reflects continual community-driven efforts to make ncORFs accessible and actionable to the broader research public and further iterations of the catalog will continue to expand and refine this resource. ### Competing Interest Statement J.R.P. has received research honoraria from Novartis Biosciences and Quantum-Si, and is a paid consultant for ProFound Therapeutics. J.L.A. is an advisor to Microneedle Solutions. G.M. is co-founder and CSO of OHMX.bio. P.F. is a member of the scientific advisory board of Infinitopes. A.-R. C. is a member of the advisory board of ProFound Therapeutics. P.V.B. is a cofounder and shareholder of Eirnabio Ltd.

Background For decades, vast stretches of the genome were dismissed as non-functional ‘junk’. However, our group and others have revealed that these regions harbor numerous non-canonical open reading ...

Background For decades, vast stretches of the genome were dismissed as non-functional ‘junk’. However, our group and others have revealed that these regions harbor numerous non-canonical open reading ...

Innovations in the pallium likely facilitated the evolution of advanced cognitive abilities in birds. We therefore scrutinized its cellular composition and evolution using cell type atlases from chick...

The human genome encodes potentially thousands of tiny proteins that were previously overlooked. The search is on to find out what they do.

The human genome encodes potentially thousands of tiny proteins that were previously overlooked. The search is on to find out what they do.

The human genome encodes potentially thousands of tiny proteins that were previously overlooked. The search is on to find out what they do.

Background Over recent years, the van Heesch lab has discovered thousands of new “non-canonical” open reading frames (ncORFs) translated from regions of the genome believed not to code for protein. Ma...

Wij doen als team mee aan Alpe d’HuZes omdat wij geloven dat wij samen kunnen werken aan een wereld waarin je niet meer doodgaat aan kanker, wil jij ons steunen?

The 2025 Gordon Research Conference on Decoding Microproteins Across Evolution and Disease will be held in Castelldefels, Barcelona Spain. Apply today to reserve your spot.

Sandmann et al. explore the evolution and interactomes of the smallest and evolutionarily youngest members of the human proteome. They identify previously unknown human short ORF-encoded microproteins...