Isolation and chromosomal localization of the human cone cGMP phosphodiesterase gamma cDNA (PDE6H)

By comparing lists of 3'-directed partial cDNA sequences (gene signatures) randomly collected from various tissues, genes unique to each tissue can be identified. A full-size cDNA clone, corresponding to one such tissue-specific gene signature that recurred only in a retina library, was isolated and analyzed. This clone encoded 83 amino acids highly homologous to the bovine blue cone cGMP phosphodiesterase gamma subunit. The retina-specific expression of this gene was confirmed by multiple tissue Northern blotting, and its cone specificity was confirmed by in situ hybridization to a human retina specimen. From these results, we concluded that this clone (HGMW-approved symbol PDE6H) encodes for the gamma subunit of human cone-specific cGMP phosphodiesterase, and it was assigned to chromosome 12p13 by fluorescence in situ hybridization.