What does Dr. Ana Stelline know in the movie Blade Runner 2049?

I've only just seen the movie so I haven't had multiple viewings to reinforce anything but speaking from first impressions, I believe that she does know her past.

In talking with K he asks her if any of the implanted memories are someone's real memories and she indicated that using real memories is illegal. But, as it turns out, the memory of the horse is actually her memory. I believe that she actually used the memory in blade runners as a form or protection -- if one of them actually started hunting her, he might run across the date on the tree and associate with the date on the horse just as K did (interestingly, when I saw K's reaction to the date and his flashback to the horse -- my first thought was "Trojan horse"). Then, having made that association he might come to think that he is the missing child, just as K did throwing him off her trail.

When K came to her about his memory and she realized what memory he was having she seemed visibly shaken, as if things had gotten much too close to home and perhaps her ruse might not work.