Human color vision is based on three light-sensitive pigments. The isolation and sequencing of genomic and complementary DNA clones that encode the apoproteins of these three pigments are described. The deduced amino acid sequences show 41 +/- 1 percent identity with rhodopsin. The red and green pigments show 96 percent mutual identity but only 43 percent identity with the blue pigment. Green pigment genes vary in number among color-normal individuals and, together with a single red pigment gene, are proposed to reside in a head-to-tail tandem array within the X chromosome.

A recombinant DNA strategy has been used systematically to survey the Mycobacterium tuberculosis genome for sequences that encode specific antigens detected by monoclonal antibodies. M. tuberculosis genomic DNA fragments with randomly generated endpoints were used to construct a large Xgtll recombinant DNA expression library. Sufficient numbers of recombinants were produced to contain inserts whose endpoints occur at nearly every base pair in the pathogen genome. Protein antigens specified by linear segments of pathogen DNA and produced by the recombinant phage of Escherichia coli were screened with monoclonal antibody probes. This approach was coupled with an improved detection method for gene isolation using antibodies to clonally isolate DNA sequences that specify polypeptide components of M. tuberculosis. The methodology described here, which is applicable to other pathogens, offers possibilities for the development of more sensitive and specific immunodiagnostic and seroepidemiological tests for tuberculosis and, ultimately, for the development of more effective vaccines.