A lambda gt10 BXSB spleen cDNA library was screened with a DNA probe for the C kappa region. Forty individual C kappa+ phages were tested for hybridization with DNA probes representing 11 V kappa region groups. Of the phage inserts large enough to contain V kappa region sequences, 3 were negative for hybridization with all 11 V kappa region probes. The inserts from those three were subcloned, sequenced, and compared with V kappa region sequences in the gene bank. One was identical to 87.92.6 for the region sequenced (a member of V kappa RF). The second showed 93.8% sequence similarity with AN04 and called V kappa 32. The third called V kappa 33 showed 76% sequence similarity with the human sequence V52 and 73.2% sequence similarity with the mouse sequence L6. An insert from V kappa 32 containing the 5' untranslated regions through the codon for Cys 88 of the V kappa region was used as a probe in Southern blot analysis of genomic DNA from inbred and congenic strains of mice. V kappa 32 is a four to eight member group and some of the members are retained in the B6.PL-Ly2a congenic and missing from the B6.PL (85NS) congenic consistent with a map location near V kappa 28. The same filters were hybridized with the insert from V kappa 33 containing 5' untranslated region through the codon for Ser 93 of the V kappa region. V kappa 33 is a one to three member group and using the B6.PL congenics maps with the polymorphic fragments of V kappa 32 and V kappa 28.