Changes to Principal:M isoforms are based on known protein structure and funcional domains, and cross-species conservation, as well as RNA-Seq and proteomics evidence.

Principal isoforms changed by manual curation are now targged as "Alternative:M".

For DCD, the Principal:2 isoform was the isoform with the intact Pfam domain. Unfortunately, the Pfam domain was based on erroneous transcript predictions in primates.

Structure and function is known for the 110 aa protein (Principal:M), while the 121 aa protein (Alternative:M) is uninteresting.

Users of APPRIS may have noticed that there is a new category of principal isoforms, Principal:M.

These principal isoforms are exclusive to the human gene set and are principal isoforms that have been manually corrected. In GENCODE v47 there were 45 genes with Principal:M isoforms.

Here is DCD:

Nice try, Luka. But even in a sham election with the real opposition candidates in jail, that is still some way short. of the 99.86% of supported ClinVar pathogenic mutations that map to APPRIS principal isoforms ...