IFN-α1a Gene Is the Major Variant in the North American Population

Abstract

Thirteen interferon (IFN)-α functional genes have been reported. A number of these genes have allelic members (variants). In the case of IFN-α1, two variants, IFN-α1a and IFN-α1b, are known. The variants differ 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-α1 gene(s) using polymerase chain reaction (PCR). Genomic DNA, obtained from over 23,000 normal healthy individuals and from four human cell lines, were used as templates in PCR to amplify the IFN-α1 gene sequences. The resulting PCR products were analyzed by restriction endonuclease digestion and DNA sequencing to identify the presence of variant sequences. The results show that IFN-α1a is predominant in the genomic DNA of the population examined. Among the cell lines studied, IFN-α1a is the only variant found in U-937 and Namalwa cells, whereas KG-1 cells have only IFN-α1b, and EB-3 cells have both IFN-α1a and IFN-α1b in the genome.