INTERFERON-ALPHA(2) VARIANTS IN THE HUMAN GENOME

Variants of human leukocyte interferon alpha(2) (IFN-alpha(2a), alpha( 2b), and alpha(2c)) differ from each other by changes in their coding regions at nucleotide positions 137 and 170. As a result of these nucl eotide variations, the DNA sequences of the three variants can be dist inguished by selective restriction enzyme analysis. Human genomic DNA obtained from over 28,000 normal healthy individuals was used as templ ates in the polymerase chain reaction (PCR) to amplify the human IFN-a lpha(2) gene sequence. The resulting PCR products were analyzed with r estriction nucleases to identify the specific IFN-alpha(2) variant seq uences present in the genomic DNA of the population examined, The resu lts show that IFN-alpha(2b) was detected as the predominant species an d IFN-alpha(2c) as a very minor species (<0.1%). The IFN-alpha(2a) gen e was not detected in this population.