Here is the link to the UniProt ID A0N5G1_HUMAN: 
https://www.uniprot.org/uniprot/A0N5G1

I could maximum find this :https://www.ebi.ac.uk/ena/data/view/AAB25742\

Could not find much on this. Any leads will be appreciable. 
I am assuming this gene is submitted but under review at transcript level, hence we do not find any associated gene symbol, but I may be wrong. Any insights will be very much appreciated.

P.S.: Posted the link of this Biostar query in Twitter to see if someone responds to the thread. 
Got your query from Twitter :)

This is a TrEMBL [entry][1], meaning an unreviewed sequence with low quality and scored poorly according to UniProt [association score][2] rules. It gives no results in Ensembl (at least for [human][3]), Entrez [Gene][4] or [Open Targets Platform][5], which leads me to believe it's not been used for gene/transcript annotation. 

I have also downloaded [all the genes associated with rheumatoid arthritis][6] hoping to get the gene name picked up from text mining or elsewhere but no luck. And [LINK][7] (that allows us to explore connections for genes from millions of PubMed abstract documents and semantic relationships) but still no luck. You may want to delve deeper in the relations for [Rheumatoid][8] only in LINK though. 

How about contacting [UniProt][9] helpdesk to clarify on this?


  [1]: https://www.uniprot.org/uniprot/A0N5G1#entry_information
  [2]: https://www.uniprot.org/help/annotation_score
  [3]: https://www.ensembl.org/Human/Search/Results?q=A0N5G1;facet_feature_type=;site=ensembl;facet_species=Human
  [4]: https://www.ncbi.nlm.nih.gov/gene/?term=A0N5G1
  [5]: https://www.targetvalidation.org/search?src=q:A0N5G1
  [6]: https://www.targetvalidation.org/disease/EFO_0000685/associations
  [7]: http://blog.opentargets.org/2018/01/18/link/
  [8]: https://link.opentargets.io/view?query=rheumatoid
  [9]: https://www.uniprot.org/contact