title: Identification of novel SNP in caprine β-lactoglobulin gene.
abstract: β-lactoglobulin (β-LG) gene is suggested as a functional candidate gene for milk yield and milk composition. β-LG polymorphism has been reported to be associated with milk yield in cows, sheep and Indian goats. This study was performed to identify SNPs in exon 7 of β-LG gene and their association with milk traits in Iranian local Mahabadi goats using polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) and PCR-sequencing. Three SSCP patterns were observed with frequencies 0.678, 0.096 and 0.226, respectively. Subsequently, after sequencing each unique pattern nine novel mutations were identified. These mutations include: T InDel at nucleotide position 93 and substitutions T/C, T/G, T/C, G/T, T/G,T/C, G/A and A/T at nucleotide positions 99, 124, 126, 134, 147, 156, 176 and 177, respectively. Of these, seven mutations were same among the genotypic patterns while differences were related to T deletion and insertion (-/T) at nucleotide position 93 with frequencies 0.22 and 0.78 in the presence and absence of T allele, respectively; and substitution (A/T) at nucleotide position 177 with frequencies 0.16 and 0.84 for A and T alleles, respectively. Milk traits including milk production (gr), milk fat and protein (%) were also measured. These findings demonstrated that β-LG gene had a significant effect on milk protein percentage (P < 0.05), but had no significant effect on milk production and milk fat percentage.
authors.affiliation: Department of Animal Science University College of Agriculture and Natural Resources, University of Tehran, Karaj 3158711167, Iran. hmoradis@ut.ac.ir.
authors.forename: Leila
authors.initials: L
authors.lastname: Gharedaghi
authors.forename: Hosein Moradi
authors.initials: HM
authors.lastname: Shahrbabak
authors.forename: Mostafa
authors.initials: M
authors.lastname: Sadeghi
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D005838:Genotype; D006041:Goats / Q000235:genetics*; D054643:INDEL Mutation; D007774:Lactation / Q000502:physiology; D007782:Lactoglobulins / Q000235:genetics*; D008055:Lipids / Q000032:analysis; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000032:analysis; D017354:Point Mutation; D020641:Polymorphism, Single Nucleotide; D018807:Polymorphism, Single-Stranded Conformational; D019655:Quantitative Trait, Heritable; D016415:Sequence Alignment
chemical_list: D007782:Lactoglobulins; D008055:Lipids; D008894:Milk Proteins