The immunoglobulin gene system in reptiles has not been as well investigated as that of other species. Studies of the genomic libraries of the rearranged and unrearranged DNA of a turtle revealed a number of distinctions in both the arrangement and the function of the variable region. Although at least four Vh gene groups have been found, each consisting of hundreds of gene segments, only one group seems to be expressed.To explore this possibility further, anchored PCR was performed on RNA obtained from the liver of a turtle using a primer in Cμ, in order to procure an unbiased variety of rearrangements. Sequences were isolated through the use of a probe specific for the constant region, and examined for Vh family relationships. We also isolated a genomic Jh sequence and obtained genomic VDJ rearrangements by PCR from splenic DNA. Analysis of junctional diversity revealed 23 out of 25 rearrangements that were in frame, and the two that were non-functional involved Dh genes at least 45 bp in size.