Everyone else already answered your question, but I just wanna throw something in
Usually (at least, as far as I know), it's obvious if a Syrian is male because they drag their, uh, bits behind them. So you could look out for that. Also, I think hamsters can't really control/care where they poo, as Spunky certainly didn't (poo everywhere, esp. at his nest!) Spunky did apparently control where he peed, though.