title: Haplotype analysis of the human collectin placenta 1 (hCL-P1) gene.
abstract: Collectins are a family of C-type lectins found in vertebrates. These proteins have four regions, a relatively short N-terminal region, a collagen-like region, an alpha-helical coiled coil, and a carbohydrate recognition domain. Collectins are involved in host defense through their ability to bind carbohydrate antigens on microorganisms. Type A scavenger receptors are classical-type scavenger receptors that also have collagen-like domains. We previously described a new scavenger receptor, collectin from placenta [collectin placenta 1 (CL-P1)]. CL-P1 is a type II membrane protein with all four regions. We found that CL-P1 can bind and phagocytize both bacteria and yeast. In addition to that, it reacts with oxidized low-density lipoprotein (LDL) but not with acetylated LDL. These results suggest that CL-P1 might play important roles in host defenses and/or atherosclerosis formation. One rational strategy to study the role of CL-P1 in these pathological conditions would be to perform a haplotype association study using human samples. As a first step for this strategy, we analyzed the haplotype structure of the CL-P1gene. By sequencing the CL-P1 gene in ten Japanese volunteers, we identified five single-nucleotide polymorphisms (SNPs) with a minor allele frequency of at least 29%. To obtain SNPs in the 5'-upstream region of the gene, we screened a total of 20 SNPs described in the database and finally picked up one SNP for the present study. Thus, a total of six SNPs, one in the 5'-upstream region, two in intron 2, one in exon 5, and two in exon 6, were used to analyze the haplotype structure of the gene, with DNAs derived from 54 individuals (108 alleles). The analysis revealed that only two of six SNPs showed significant linkage disequilibrium ( r(2) > 0.5) with each other. This haplotype information may be useful in disease-association studies in which a contribution of the CL-P1 gene has been suspected, especially in immunological disturbance or atherosclerosis. Two SNPs in exon 6, both leading to amino acid substitutions, could be candidates for influencing disease susceptibility.
authors.affiliation: Department of Public Health, Asahikawa Medical College, 2-1-1-1 Midorigaoka-higashi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohmori
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Makita
authors.forename: Makiko
authors.initials: M
authors.lastname: Funamizu
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Chiba
authors.forename: Katsuki
authors.initials: K
authors.lastname: Ohtani
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Wakamiya
authors.forename: Akira
authors.initials: A
authors.lastname: Hata
mesh_terms: D019943:Amino Acid Substitution; D037222:Collectins / Q000235:genetics*; D005787:Gene Frequency; D005838:Genotype; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007564:Japan; D015810:Linkage Disequilibrium; D020641:Polymorphism, Single Nucleotide; D011971:Receptors, Immunologic / Q000235:genetics*; D051116:Receptors, Scavenger
chemical_list: C422442:COLEC12 protein, human; D037222:Collectins; D011971:Receptors, Immunologic; D051116:Receptors, Scavenger