Nav2 protein coding gene O neuron navigator 2 RAINB2 Gene MGI:2183691 genetic mapping Unc53H2|RAINB2|HELAD1|Rainb1|POMFIL2|5330421F07Rik POMFIL2 5330421F07Rik HELAD1 http://identifiers.org/mgd/MGI:2183691 Unc53H2 + Rainb1