Are you afraid of the consequences if there were differences to be found? That's what you're saying?Yes I have. Pursuing a thoroughly debunked theory is suspicious. Your motives are suspicious. Even if you came up with a new, previously unconsidered angle, I'd question your motives and to what use the knowledge could be put. Which you've not answered.
Your pure and untainted motives for wanting to know if some races are inferior are not even remotely believable.