Vλ and Jλ‐Cλ gene segments of the human immunoglobulin λ light chain locus are separated by 14 kb and rearrange by a deletion mechanism

Publisher Website
Google Scholar
Abstract
We have cloned a region of 124 kb of the human immunoblogulin λ light chain locus on chromosome 22 encompassing seven Vλ and seven J‐Cλ gene segments. No further Cλ gene segment was found in a region of 35 kb downstream of Cλ7, which encodes the Ke+Oz− isotype. The Cλ proximal Vλ gene segment VλIII. 1 is located 14.5 kb upstream of Cλ1. The five sequenced Vλ genes have the same transcriptional orientation as the J‐Cλ gene segments which is likely to be true for the majority of the Vλ gene segments in the human λ locus and which suggests a deletion mechanism for DNA rearrangement. This is supported by hybridization of Vλ gene probes to germ‐line and rearranged DNA from λ light chain‐producing cell lines. Sequences of 23 cDNA clones allow to establish a Vλ subgroup classification based on nucleic acid sequence data and an estimate of the J‐Cλ usage.