IFN-alpha 1a gene is the major variant in the North American population

Thirteen interferon (IFN)-alpha functional genes have been reported. A numb er of these genes have allelic members (variants), In the case of IFN-alpha 1, two variants, IFN-alpha 1a and IFN-alpha 1b, are known. The variants di ffer from each other by one base change in the coding region, leading to a single change in amino acid sequence and the presence of a restriction site . We have developed oligonucleotide primers for amplification of IFN-alpha 1 gene(s) using polymerase chain reaction (PCR), Genomic DNA, obtained from over 23,000 normal healthy individuals and from four human cell lines, wer e used as templates in PCR to amplify the IFN-alpha 1 gene sequences. The r esulting PCR products mere analyzed by restriction endonuclease digestion a nd DNA sequencing to identify the presence of variant sequences. The result s show that IFN-alpha 1a is predominant in the genomic DNA of the populatio n examined. Among the cell lines studied, IFN-alpha 1a is the only variant found in U-937 and Namalwa cells, whereas KG-1 cells have only IFN-alpha 1b , and EB-3 cells have both IFN-alpha 1a and IFN-alpha 1b in the genome.