VH gene family utilization is regulated by a locus outside of the VH region

We have used the RNA colony blot method to examine VH usage in colonies derived from primary splenic B cells. We found that there are strain-specific differences in the pattern of VH usage. Using parental F1, congenic, and recombinant inbred strains we demonstrate that the genetic element that causes the observed phenotype is: (a) stably expressed; (b) not due to maternal influence; (c) not due to dominate diffusible factors; (d) not linked to cloning efficiency; and (e) outside the Igh locus.