title: Association of neuropeptide Y and gonadotrophin-releasing hormone receptor gene SNPs  with breeding value for growth and egg production traits in Mazandaran native chickens.
abstract: Neuropeptide  Y (NPY) and gonadotrophin-releasing hormone receptor (GnRHR) are two candidate  genes with a wide variety of physiological functions in growth and especially  in reproduction processes. We examined the association of one SNP from each of  these genes with growth- and egg production-related traits in Mazandaran native  chickens. Two hundred and six individuals were genotyped by PCR-RFLP.  Marker-trait association analyses were performed using both breeding value and  phenotypic information. The data came from 18 successive generations of  selection at a Mazandaran native chicken breeding station in Iran. Data were  analyzed with a univariate animal model in an ASREML procedure to estimate  breeding values of the birds for these traits. Two alleles were found for both  genes, A and a alleles for GnRHR, with frequencies of 0.614 and 0.386, B and b  alleles for NPY, with frequencies of 0.780 and 0.221, respectively. The  additive genetic effects of the GnRHR gene on egg number and egg mass were  significant. Also, body weight at sexual maturity was significantly influenced  by the NPY gene. We conclude that GnRHR and NPY genes are associated with egg  production and growth traits, respectively.
authors.affiliation: Department of Animal Science, University College of Agricultural and Natural Resources, University of Tehran, Karaj, Iran.
authors.forename: S A
authors.initials: SA
authors.lastname: Fatemi
authors.forename: H
authors.initials: H
authors.lastname: Mehrabani-Yeganeh
authors.forename: A
authors.initials: A
authors.lastname: Nejati-Javaremi
authors.forename: Sh
authors.initials: Sh
authors.lastname: Niknafs
mesh_terms: D000818:Animals; D001947:Breeding; D002645:Chickens / Q000235:genetics* / Q000254:growth & development*; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D056726:Genetic Association Studies; D005819:Genetic Markers; D005838:Genotype; D007492:Iran; D008297:Male; D009478:Neuropeptide Y / Q000235:genetics*; D010063:Ovum / Q000254:growth & development* / Q000378:metabolism; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D011966:Receptors, LHRH / Q000235:genetics*
chemical_list: D005819:Genetic Markers; D009478:Neuropeptide Y; D011966:Receptors, LHRH