Intergenic exchange maintains identity between two human lambda light chain immunoglobulin gene intron sequences.

J A Udey; B B Blomberg

doi:10.1093/nar/16.7.2959

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Intergenic exchange maintains identity between two human lambda light chain immunoglobulin gene intron sequences.

J A Udey·B B Blomberg

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Abstract

Evidence for gene conversion or unequal double crossover in the human lambda light chain immunoglobulin locus is presented. The high level of J2C2-J3C3 intron cross-hybridization, the identity of the J lambda and J lambda 3 coding and intron sequences, the presence of multiple base differences between the C lambda 2 and C lambda 3 coding regions, and the presence of both the unconverted and converted alleles in the normal gene pool, suggest that a recombinational event has resulted in the conversion of the J lambda 2 coding and intron sequences to those of J lambda 3 and its flanking sequences. Intergenic exchanges, such as the one described here, may provide a mechanism to maintain sequence homogeneity and functionality among the duplicated members of the human lambda gene family.

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Amino Acid Sequence Base Sequence Gene Conversion Genes, Immunoglobulin Germ Cells Humans Immunoglobulin J-Chains Immunoglobulin lambda-Chains Introns Kidney Molecular Sequence Data Multigene Family Nucleic Acid Hybridization Polymorphism, Genetic Journal Article Research Support, U.S. Gov't, P.H.S.

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J A Udey, B B Blomberg. 1988-04-11. Intergenic exchange maintains identity between two human lambda light chain immunoglobulin gene intron sequences.. https://doi.org/10.1093/nar%2F16.7.2959

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