title: The isolation of a human Ig V lambda gene from a recombinant library of chromosome 22 and estimation of its copy number.
abstract: We report the first isolation and characterisation of a human Ig V lambda gene. The gene was isolated from a recombinant phage library of human chromosome 22 using a mouse Ig lambda cDNA as probe. DNA sequence analysis predicts a short leader peptide interrupted by an intron of 88 nucleotides, and a mature polypeptide of 96-97 amino acids which shares 61% homology with mouse V lambda I chains. Comparison with the amino acid sequence of known human lambda chains of all six subgroups shows agreement at 22/25 low variance positions. However the maximum homology with human chains is 49%, so we conclude that this sequence represents a new IgV lambda subgroup. The coding region is followed by the conserved heptamer, CACAGTG, and nonamer, ACATAAACC, sequences which have been implicated in V-J segment recombination. This gene has the hallmarks of an active V lambda gene including recently identified transcriptional controlling sequences. Probing genomic DNA with the subcloned V lambda gene detects a family of about 10 cross hybridizing members at low stringency and 2 at high stringency. There is limited polymorphism of the V lambda locus.
mesh_terms: D001483:Base Sequence; D002904:Chromosomes, Human, 21-22 and Y; D003001:Cloning, Molecular; D004247:DNA / Q000097:blood; D004262:DNA Restriction Enzymes; D004274:DNA, Recombinant / Q000302:isolation & purification*; D005796:Genes; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D011110:Polymorphism, Genetic
chemical_list: D004274:DNA, Recombinant; D007135:Immunoglobulin Variable Region; D004247:DNA; D004262:DNA Restriction Enzymes