title: Novel SNPs of  the mannan-binding lectin 2 gene and their association with production traits  in Chinese Holsteins.
abstract: The  mannan-binding lectin gene (MBL) participates as an opsonin in the  innate immune system of mammals, and single nucleotide polymorphisms (SNPs) in MBL cause various immune dysfunctions. In this study, we detected SNPs in MBL2 at exon 1 using polymerase chain reaction single-strand conformation  polymorphism analysis and DNA sequencing techniques in 825 Chinese Holstein  cows. Four new SNPs with various allele frequencies were also found. The g.1164  G>A SNP was predicted to substitute arginine with glutamine at the  N-terminus of the cysteine-rich domain. In the collagen-like domain, SNPs  g.1197 C>A and g.1198 G>A changed proline to glutamine, whereas SNP  g.1207 T>C was identified as a synonymous mutation. Correlation analysis  showed that the g.1197 C>A marker was significantly correlated to somatic  cell score (SCS), and the g.1164 G>A locus had significant effects on SCS,  fat content, and protein content (P < 0.05), suggesting possible roles of  these SNPs in the host response against mastitis. Nine haplotypes and nine haplotype  pairs corresponding to the loci of the 4 novel SNPs were found in Chinese  Holsteins. Haplotype pairs MM, MN, and BQ were correlated with the lowest SCS;  MN with the highest protein yield; MM with the highest protein rate, and MN  with the highest 305- day milk yield. Thus, MM, MN, and BQ are possible  candidates for marker-assisted selection in dairy cattle breeding programs.
authors.affiliation: College of Animal Husbandry and Veterinary, Jilin University, Changchun, P.R. China.
authors.forename: Z L
authors.initials: ZL
authors.lastname: Zhao
authors.forename: C F
authors.initials: CF
authors.lastname: Wang
authors.forename: Q L
authors.initials: QL
authors.lastname: Li
authors.forename: Z H
authors.initials: ZH
authors.lastname: Ju
authors.forename: J M
authors.initials: JM
authors.lastname: Huang
authors.forename: J B
authors.initials: JB
authors.lastname: Li
authors.forename: J F
authors.initials: JF
authors.lastname: Zhong
authors.forename: J B
authors.initials: JB
authors.lastname: Zhang
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics*; D002681:China; D005091:Exons / Q000235:genetics; D005787:Gene Frequency / Q000235:genetics; D056726:Genetic Association Studies; D006239:Haplotypes / Q000235:genetics; D006579:Heterozygote; D016018:Least-Squares Analysis; D037601:Mannose-Binding Lectin / Q000737:chemistry / Q000235:genetics*; D008892:Milk / Q000378:metabolism*; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D018807:Polymorphism, Single-Stranded Conformational / Q000235:genetics; D019655:Quantitative Trait, Heritable; D017422:Sequence Analysis, DNA; D016622:Silver Staining
chemical_list: D037601:Mannose-Binding Lectin