Immunogen sequence: MRRSVAAGGG GGSGKTRTKD KYRVVYTDHQ RLELEKEFHY SRYITIRRKS ELAANLGLTE RQVKIWFQNR RAKERKVNKK KQQQQQPPQP PMAHDITATP AGPSLGGLCP SNTSLLATSS PMPVKEEFLP. CDX1, or caudal type homeobox 1, is a gene encoding a homeodomain transcription factor tha