Try EK, which I believe is the only one-stop option for this route. Not the best connection in DXB on the outbound though: EK212 IAH-DXB arrives 1845, EK420 DXB-PER departs 0255. The return is better: EK421 PER-DXB arrives 0530, EK211 DXB-IAH departs 0905.