title: Discovery of two novel variants of KIR2DS5 reveals this gene to be a common component of human KIR 'B' haplotypes.
abstract: The gene encoding the non-inhibitory receptor KIR2DS5 has so far been represented by a single cDNA sequence, NKAT9. A previous study by polymerase chain reaction using sequence-specific primers (PCR-SSP) failed to detect NKAT9 in genomic DNA of 52 donors, which suggested that KIR2DS5 could be a rare gene. Here, we have characterized two novel variants of KIR2DS5 that differ from NKAT9 by 8 and 10 nucleotide substitutions. The frequency of KIR2DS5 was then re-assessed by PCR-SSP using primers specific for conserved sequences of all three known KIR2DS5 variants. We found KIR2DS5 is not a rare gene, but one present in 26% of 34 donors representing the major ethnic groups. Like other non-inhibitory KIR, the distribution of KIR2DS5 is restricted to the 'B' subset of KIR-gene haplotypes. Transcription of the KIR2DS5 gene was studied by reverse transcriptase (RT)-PCR in natural killer (NK) cells from one donor and shown to follow the clonal distribution seen for most other KIR genes.
authors.affiliation: Department of Structural Biology, Stanford University School of Medicine, California 94305, USA.
authors.forename: C
authors.initials: C
authors.lastname: Vilches
authors.forename: M J
authors.initials: MJ
authors.lastname: Pando
authors.forename: R
authors.initials: R
authors.lastname: Rajalingam
authors.forename: C M
authors.initials: CM
authors.lastname: Gardiner
authors.forename: P
authors.initials: P
authors.lastname: Parham
mesh_terms: D014644:Genetic Variation; D006239:Haplotypes; D006801:Humans; D007694:Killer Cells, Natural / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000145:classification / Q000235:genetics*; D054340:Receptors, KIR
chemical_list: D011971:Receptors, Immunologic; D054340:Receptors, KIR