God's Quiz

Both dramas are about solving cases by finding the cause or disease (DF - Psychology , GQ - Rare diseases during Autopsy)
Both are of the same channel OCN
Both dramas have suspense, thriller & serial killer in between
Both ML has a past which they don't share to others easily
Both ML are well known genius at very young age in their professional fields
If you liked Dr Frost I strongly suggest to watch God's Quiz which has total 5 Season episodes

This is the first season of God's Quiz.
Season 1 is more difficult to understand because you don't get extra subtitle or anything about the special illness.