Gene serine/arginine-rich splicing factor 4 + SRp75|Sfrs4|MNCb-2616|5730499P16Rik MNCb-2616 O SRp75 Sfrs4 http://identifiers.org/mgd/MGI:1890577 Srsf4 protein coding gene 5730499P16Rik MGI:1890577 genetic mapping