A simple method of screening for the common connexin-26 gene 35delG mutation in nonsyndromic neurosensory autosomal recessive deafness

Mutations in the Connexin-26 gene are responsible for up to 60% of nonsyndromic, neurosensory autosomal recessive deafness (NSRD). Amongst all the mutations described to date, 35delG (a deletion of a G in a tract of five Gs at positions 30-35) is the most common and has been found in virtually all of the populations studied. Because its frequency varies in different populations, a rapid and simple method of detection of this mutation would be very helpful in population studies. A wide variety of methods for this detection have been described, but we herein present a very simple method using a PCR with primers designed to provide an amplicon of 94 or 93 nucleotides for the normal or mutant alleles, respectively, that can be easily distinguished in an 8% polvacrylamide gel. The entire protocol can be completed in a morning, thus supporting multiple runs. This assay will be useful in screening the large sample sizes required for population studies.