A QUANTITATIVE AND SPECIFIC METHOD FOR MEASURING TRANSCRIPT LEVELS OFHIGHLY HOMOLOGOUS GENES

Because of their high nucleotide sequence homology, the specific detec tion of mRNA transcripts of individual members of a gene family presen ts certain problems. Here we apply and defend the single nucleotide pr imer extension (SNuPE) as a simple, specific, and highly quantitative assay for this purpose. The method distinguishes regions of the brain sodium channel gene family that vary by as little as a single nucleoti de. The technique has been modified to include an intersample normaliz er, and adaptation of the SNuPE assay to other gene families of intere st to neuroscientists should be easy to achieve.