Halplotypes of the ovine ADRB3 gene (ADRB3) and their association with post-weaning growth in New Zealand Suffolk sheep Guo Yang • Huitong Zhou • Rachel H. Forrest • Qian Fang • Yuzhu Luo • Jon G. H. Hickford Received: 3 October 2012 / Accepted: 29 April 2013 Ó Springer Science+Business Media Dordrecht 2013 Abstract The b 3 -adrenergic receptor (ADRB3) regulates thermogenesis and lipolysis in brown and white adipose tissue. Previously, sixteen ovine ADRB3 haplotypes have been defined. In this study, the relationship between these ADRB3 haplotypes and variation in post-weaning growth was investigated in 797 New Zealand Suffolk lambs from 38 sire lines and eight studs, using PCR-SSCP and General Linear Mixed-effects Models. Seven haplotypes were found in these sheep and they comprised five previously reported intron sequences and four previously reported 3 0 UT sequences. The frequencies of the various diplotypes ranged from 0.1 to 17.6 % and individual haplotypes from 0.8 to 32.5 %. The presence of haplotype A-b was associ- ated with a decreased weaning-weight (P = 0.001). Sheep with the B-c/F-e diplotype had a higher mean weaning- weight than those with A-b/B-c or A-b/E-e (P \ 0.05). The presence of C-a was found to be associated with increased post-weaning growth (P = 0.008), while the presence of B-c was associated with decreased post-weaning growth (P = 0.005). Sheep with A-b/C-a had higher mean post- weaning growth than those with A-b/A-b, A-b/B-c, B-c/B-c, B-c/E-e or B-c/F-e (P \ 0.05). Sheep with B-c/B-c had lower mean post-weaning growth than those with A-b/C- a or B-c/C-a (P \ 0.05). Additive effects for the different forms of the B-c haplotypes on post-weaning growth were identified. The effects of the ovine ADRB3 haplotypes on weaning-weight and post-weaning growth confirm that they could be used as a candidate gene-marker for improving sheep growth. Keywords ADRB3 Á PCR-SSCP Á NZ Suffolk sheep Á Association Á Polymorphism Á Haplotype Introduction b 3 -adrenergic receptors (ADRB3) are predominantly located on the surface of adipocytes. They are involved in the regulation of thermogenesis and lipolysis in brown and white adipose tissues in response to sympathetic stimula- tion [1, 2]. Variation in the human ADRB3 gene (ADRB3) has been associated with an impaired ability to produce intracellular cAMP [3], altered lipolytic glycerol levels [4] and subse- quently varied energy homeostasis phenotypes including risk of type II diabetes (NCBI OMIM No. 109691), abdominal obesity [5] and weight gain [6]. Variation in both the coding and non-coding regions of ovine ADRB3 (located on ovine chromosome 26, OAR26) has been reported previously [7–11]. Of this, variation in the intron of ovine ADRB3 have been associated variously with variation in pre-weaning growth rate in Merino-cross (x Coopworth and Dorset Down) sheep and NZ Romney sheep [7, 12], carcass composition in Merino-cross (x Coopworth and Dorset Down) sheep [7], cold survival in Merino-cross (x Coopworth and Dorset Down) sheep [7], Merino sheep [13] and eleven other crosses of NZ meat and wool breeds [14] and wool staple-strength in Merino sheep [15]. Recently, we reported variation in the 3 0 untranslated region (3 0 UT) of ovine ADRB3 and deduced sixteen G. Yang Á R. H. Forrest Á Y. Luo (&) Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou, China e-mail: luoyz@gsau.edu.cn H. Zhou Á R. H. Forrest Á Q. Fang Á J. G. H. Hickford (&) Agriculture and Life Sciences Division, Lincoln University, PO Box 84, Lincoln 7647, New Zealand e-mail: jon.hickford@lincoln.ac.nz 123 Mol Biol Rep DOI 10.1007/s11033-013-2576-5