DRD4 and cancer: In the chromosomal region 7q32.1–7q36.3, in addition to NRF-1 and BRAF, involved in several cancers [31], there are another 2 interesting genes, namely EPHB6 (whose levels have been proposed as prognostic indicators in NB [32]), and EZH2 (which plays an essential role in the control of the central nervous system by regulating the dopamine D4 receptor [33]).