scription products predicts a relatively simple relationship
between the organization of the gene and its protein product.
The three exons that comprise the c-myc gene in human,
avian, feline, and rodent cells contain only one long
translational open reading frame (ORF) beginning with an
ATG. This highly conserved c-myc ORF begins near the
5’ end of exon 2 and extends through approximately twothirds
of exon 3. It is noteworthy that no ATG codons in any
reading frame can be found among the many available
exon 1 nucleotide sequences. Thus normal c-myc mRNAs
that contain the first exon would be expected to possess
a substantial untranslated leader region preceding the
ORF