Patent ID: 7056672

Claim:
A method for determining the presence or absence of an open reading frame in a nucleic acid molecule among a population of nucleic acid molecules, said method comprising: a) inserting said nucleic acid molecule into a vector, said vector comprising an nucleic acid sequence, wherein said nucleic acid sequence comprises three start codons within a span of 50 nucleotides, wherein each said start codon is within a different reading frame, wherein said nucleic acid sequence encodes histidine tags in three reading frames, wherein said nucleic acid molecule is inserted into said vector such that said nucleic acid molecule is 3′ or 5′ of said nucleic acid sequence encoding said histidine tags; b) introducing the resulting vector into a host cell; c) culturing said host cell under conditions permitting expression of said nucleic acid molecule; d) determining the presence or absence of a histidine tagged polypeptide encoded by said nucleic acid molecule, the presence of a histidine tagged polypeptide indicating that said nucleic acid molecule has an open reading frame.