https://en.m.wikipedia.org/wiki/Middle_East_respiratory_synd...
This is a dangerous difference.
> SARS-CoV recognizes angiotensin-converting enzyme 2 (ACE2) as its receptor, whereas MERS-CoV recognizes dipeptidyl peptidase 4 (DPP4) as its receptor.
That's what was being researched in Wuhan from what I've read in the media.
The ACE2 receptor affinity is not novel.
The 2004 SARS was suspected to be lab leak. (I'm not sure if this conclusion has been revised since.)