Nucleotide sequence of the human c‐myc locus: provocative open reading frame within the first exon

The nucleotide sequence of a HindIII‐EcoRI DNA fragment, 8 kbp long, of a lambda recombinant containing the whole human c‐myc gene has been deduced by the method of Maxam and Gilbert. This fragment encodes the complex c‐myc locus and the sequence provides information relative to the 2.7 kb long c‐myc transcript. It appears that although exons 2 and 3 would code for a 48‐K protein homologous to the myc domain of the viral p110 gag‐myc protein, the first exon, which has a large open reading frame ending with a stop codon just upstream from the donor splice site, could code on its own for a 20‐K protein. Speculations about the role of that putative protein on the regulation of the expression of exons 2 and 3 are made.