Allotype-specific probes. A molecular approach to the study of serologically defined determinants

A new approach to the study of serologically defined immunoglobulin determinants is described. We designed DNA probes which distinguished between the rabbit kappa light chain allotypic sequences in Northern analyses of mRNAs and Southern analyses of genomic DNAs. S1 nuclease protection experiments are described which detect allotype-specific sequences in as little as 100 pg of total RNA. The use of molecular biological techniques overcomes many of the problems inherent in using serological reagents and techniques. In addition, the sensitivity of the assays described here allows the detection of low level expression of the allotypic genes. This work was extended to include the discrimination of the VHa allotypes.