The Hox-1.4 murine homeo box containing gene is expressed in both embryonic spinal cord and adult testis where different sized Hox-1.4 transcripts are detected. In order to compare the sequences of these transcripts, Hox-1.4 cDNA clones were isolated from cDNA libraries prepared from mouse embryonic spinal cord and mouse adult testis. Sequence analysis showed these clones to be identical and extend from an internal EcoRI site at position 55 in the homeo box to a poly (A) stretch 20 nucleotides 3' to the polyadenylation signal. These data indicate that murine Hox-1.4 mRNAs expressed in embryonic spinal cord and adult testis are identical 3' to the homeo box and utilize the same polyadenylation signal.