code=Dispatch@{​​"A"{1,1,1},​​"C"{-1,1,-1},​​"G"{-1,-1,1},​​"T"{1,-1,-1}​​};
In[]:=
colors=Dispatch@{"A"Red,"C"Green,"G"Blue,"T"Yellow};
In[]:=
Graphics3D[​​Line[FoldList[Plus,#/.code],VertexColors(#/.colors)]&[​​Characters@GenomeData["HOXA1","FullSequence"]​​]​​]
Out[]=