title: Genome-wide association studies for growth and meat production traits in sheep.
abstract: BACKGROUND
  Growth and meat production traits are significant economic traits in sheep. The aim of the study is to identify candidate genes affecting growth and meat production traits at genome level with high throughput single nucleotide polymorphisms (SNP) genotyping technologies.
  
  
  RESULTS
  Using Illumina OvineSNP50 BeadChip, we performed a GWA study in 329 purebred sheep for 11 growth and meat production traits (birth weight, weaning weight, 6-month weight, eye muscle area, fat thickness, pre-weaning gain, post-weaning gain, daily weight gain, height at withers, chest girth, and shin circumference). After quality control, 319 sheep and 48,198 SNPs were analyzed by TASSEL program in a mixed linear model (MLM). 36 significant SNPs were identified for 7 traits, and 10 of them reached genome-wise significance level for post-weaning gain. Gene annotation was implemented with the latest sheep genome Ovis_aries_v3.1 (released October 2012). More than one-third SNPs (14 out of 36) were located within ovine genes, others were located close to ovine genes (878bp-398,165bp apart). The strongest new finding is 5 genes were thought to be the most crucial candidate genes associated with post-weaning gain: s58995.1 was located within the ovine genes MEF2B and RFXANK, OAR3_84073899.1, OAR3_115712045.1 and OAR9_91721507.1 were located within CAMKMT, TRHDE, and RIPK2 respectively. GRM1, POL, MBD5, UBR2, RPL7 and SMC2 were thought to be the important candidate genes affecting post-weaning gain too. Additionally, 25 genes at chromosome-wise significance level were also forecasted to be the promising genes that influencing sheep growth and meat production traits.
  
  
  CONCLUSIONS
  The results will contribute to the similar studies and facilitate the potential utilization of genes involved in growth and meat production traits in sheep in future.
authors.affiliation: Animal Genetics and Breeding Department, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China. zhangli@263.net
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Jiasen
authors.initials: J
authors.lastname: Liu
authors.forename: Fuping
authors.initials: F
authors.lastname: Zhao
authors.forename: Hangxing
authors.initials: H
authors.lastname: Ren
authors.forename: Lingyang
authors.initials: L
authors.lastname: Xu
authors.forename: Jian
authors.initials: J
authors.lastname: Lu
authors.forename: Shifang
authors.initials: S
authors.lastname: Zhang
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Zhang
authors.forename: Caihong
authors.initials: C
authors.lastname: Wei
authors.forename: Guobin
authors.initials: G
authors.lastname: Lu
authors.forename: Youmin
authors.initials: Y
authors.lastname: Zheng
authors.forename: Lixin
authors.initials: L
authors.lastname: Du
mesh_terms: D000818:Animals; D001835:Body Weight / Q000235:genetics; D005260:Female; D056426:Genetic Loci / Q000235:genetics; D055106:Genome-Wide Association Study; D060005:Genotyping Techniques; D006801:Humans; D008297:Male; D008460:Meat; D009154:Mutation; D009929:Organ Size / Q000235:genetics; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D011786:Quality Control; D012756:Sheep / Q000235:genetics* / Q000254:growth & development*; D014886:Weaning