POU3F4 and nodular sclerosis classical Hodgkin lymphoma: The POU4F3 (POU domain, class 4, transcription factor 3) gene on 5q31 (DFNA15) is one of the two genes belonging to the superfamily of POU domain transcription factors that cause NSHL, along with POU3F4 on Xq21.1 (DFN3).