Effect of porcine IL-6 polymorphism on litter size traits in commercial pig breeds https://doi.org/10.12982/VIS.2021.021

Main Article Content

Worrarak Norseeda
Guisheng Liu
Tawatchai Teltathum
Korawan Sringarm
Watcharapong Naraballobh
Trisadee Khamlor
Patcharin Krutmuang
Supamit Mekchay


This study aimed to verify the polymorphisms in the porcine IL-6 gene and to elucidate its effects on litter size traits in Large White and Landrace sows. Four single nucleotide polymorphisms (SNPs) of the porcine IL-6 gene (g.91506415A>G, g.91507983A>G, g.91508173C>T, and g.91508716C>T) were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. There was no polymorphism observed on the three SNPs (g.91506415A>G, g.91507983A>G, and g.91508716C>T) of the porcine IL-6 gene. The porcine IL-6 g.91508173C>T polymorphism was found to be segregating in Large White and Landrace sows. The porcine IL-6 g.91508173C>T polymorphism was significantly associated with the total number born (TNB) and the number of piglets weaned alive (NWA) traits in Large White sows (P<0.05). Moreover, the porcine IL-6 g.91508173C>T polymorphism was significantly associated with the TNB, number born alive (NBA), and NWA traits in Landrace sows (P<0.05). These results indicated that the porcine IL-6 g.91508173C>T polymorphism was associated with litter size traits. These findings confirmed the importance of the IL-6 gene as a candidate gene for litter size traits in pigs.

Article Details

How to Cite
Norseeda, W. ., Liu, G. ., Teltathum, T. ., Sringarm, K. ., Naraballobh, W. ., Khamlor, T. ., Krutmuang, P. ., & Mekchay, S. . (2021). Effect of porcine IL-6 polymorphism on litter size traits in commercial pig breeds: https://doi.org/10.12982/VIS.2021.021. Veterinary Integrative Sciences, 19(2), 237–246. Retrieved from https://he02.tci-thaijo.org/index.php/vis/article/view/250549
Research Articles


Blitek, A., Morawska, E., Ziecik, A.J., 2012. Regulation of expression and role of leukemia inhibitory factor and interleukin-6 in the uterus of early pregnant pigs. Theriogenology 78, 951-964.

Bradding, P., Feather, I.H., Wilson, S., Bardin, P.G., Heusser, C.H., Holgate, S.T., Howarth,P.H., 1993. Immunolocalization of cytokines in the nasal mucosa of normal and perennial rhinitic subjects. The mast cell as a source of IL-4, IL-5, and IL-6 in human allergic mucosal inflammation. J. Immunol. 151, 3853-3865.

Burk, N.E., Vincent, A.L., Rothschild, M.F., 1997. Linkage mapping of porcine interleukin 6 (IL6). J. Anim. Sci. 75, 3367.

Chaouat, G., Dubanchet, S., Ledée, N., 2007. Cytokines: Important for implantation?. J. Assist. Reprod. Genet. 24, 491-505.

Culig, Z., Puhr, M., 2012. Interleukin-6: a multifunctional targetable cytokine in human prostate cancer. Mol. Cell. Endocrinol. 360, 52-58.

Daniłowicz, E., Akouchekian, M., Drogemuller, C., Haase, B., Leeb, T., Kuiper, H., Distl, O.,Iras, F.C., 2008. Molecular characterization and SNP development for the porcine IL6 and IL10 genes. Anim. Biotechnol. 19, 159-165.

Franczak, A., Wojciechowicz, B., Zmijewska, A., Kolakowska, J., Kotwica, G., 2013. The effect of interleukin 1β and interleukin 6 on estradiol-17β secretion in the endometrium of pig during early pregnancy and the estrous cycle. Theriogenology 80, 90-98.

Guzeloglu-Kayisli, O., Kayisli, U.A., Taylor, H.S., 2009. The role of growth factors and cytokines during implantation: endocrine and paracrine interactions. Semin. Reprod. Med. 27, 62-79.

He, L.C., Li, P.H., Ma, X., Sui, S.P., Gao, S., Kim, S.W., Gu, Y.Q., Huang, Y., Ding, N.S., Huang, R.H., 2017. Identification of new single nucleotide polymorphisms affecting total number born and candidate genes related to ovulation rate in Chinese Erhualian pigs. Anim. Genet. 48, 48-54.

Horn, F., Henze, C., Heidrich, K., 2000. Interleukin-6 signal transduction and lymphocyte function. Immunobiology 202, 151-167.

Kumchoo, T., Mekchay, S., 2015. Association of non-synonymous SNPs of OPN gene with litter size traits in pigs. Arch. Anim. Breed. 58, 317-323.

Kwon, S.G., Hwang, J.H., Park, D.H., Kim, T.W., Kang, D.G., Kang, K.H., Kim, I.S., Park, H.C., Na, C.S., Ha, J., Kim, C.W., 2016. Identification of differentially expressed
genes associated with litter size in Berkshire pig placenta. PLoS One 11, e0153311.

Laird, S.M., Tuckerman, E.M., Cork, B.A., Li, T.C., 2000. Expression of nuclear factor kappa B in human endometrium; role in the control of interleukin 6 and leukaemia
inhibitory factor production. Mol. Hum. Reprod. 6, 34-40.

Lin, H.C., Liu, G.F., Wang, A.G., Kong, L.J., Wang, X.F., Fu, J.L., 2009. Effect of polymorphism in the leukemia inhibitory factor gene on litter size in Large White pigs. Mol. Biol. Rep. 36, 1833-1838.

Martínez-Giner, M., Noguera, J.L., Balcells, I., Fernández-Rodríguez, A., Pena, R.N., 2013. Selection of internal control genes for real-time quantitative PCR in ovary and uterus of sows across pregnancy. PLoS One 8, e66023.

Modrić, T., Kowalski, A.A., Green, M.L., Simmen, R.C., Simmen, F.A., 2000. Pregnancydependent expression of leukaemia inhibitory factor (LIF), LIF receptor-beta and interleukin-6 (IL-6) messenger ribonucleic acids in the porcine female reproductive tract. Placenta 21, 345-353.

Muñoz, G., Ovilo, C., Estellé, J., Silió, L., Fernández, A., Rodriguez, C., 2007. Association with litter size of new polymorphisms on ESR1 and ESR2 genes in a ChineseEuropean pig line. Genet. Sel. Evol. 39, 195-206.

Norseeda, W., Liu, G., Teltathum, T., Sringarm, K., Naraballobh, W., Khamlor, T., Mekchay,S., 2021. Effect of leukemia inhibitory factor polymorphism on litter size traits in Thai commercial pig breeds. Vet. Integr. Sci. 19, 185-196.

Onteru, S.K., Fan, B., Du, Z.Q., Garrick, D.J., Stalder, K.J., Rothschild, M.F., 2012. A whole-genome association study for pig reproductive traits. Anim. Genet. 43, 18-26.

Paulesu, L., Jantra, S., Ietta, F., Brizzi, R., Avanzati, A.M., Bigliardi, E., 2010. Cytokines in vertebrate reproduction. Herpetol. Conserv. Biol. 5, 335-340.

Robertson, S.A., Christiaens, I., Dorian, C.L., Zaragoza, D.B., Care, A.S., Banks, A.M., Olson,D.M., 2010. Interleukin-6 is an essential determinant of on-time parturition in the
mouse. Endocrinology 151, 3996-4006.

Sherwin, J.R., Smith, S.K., Wilson, A., Sharkey, A.M., 2002. Soluble gp130 is up-regulated in the implantation window and shows altered secretion in patients with primary unexplained infertility. J. Clin. Endocrinol. Metab. 87, 3953-3960.

Song, G., Satterfield, M.C., Kim, J., Bazer, F.W., Spencer, T.E., 2009. Progesterone and interferon tau regulate leukemia inhibitory factor receptor and IL6ST in the ovine uterus during early pregnancy. Reproduction 137, 553-565.

Spötter, A., Distl, O., 2006. Genetic approaches to the improvement of fertility traits in the pig. Vet. J. 172, 234-247.

Syed, V., Ulinski, G., Mok, S.C., Ho, S.M., 2002. Reproductive hormone-induced, STAT3-mediated interleukin 6 action in normal and malignant human ovarian surface
epithelial cells. J. Natl. Cancer Inst. 94, 617-629.

Szydlowski, M., Buszka, A., Maćkowski, M., Lechniak, D., Switonski, M., 2011.Polymorphism of genes encoding cytokines IL6 and TNF is associated with pig fatness. Livest. Sci. 136, 150-156.

Uimari, P., Sironen, A., Sevón-Aimonen, M.L., 2011. Whole-genome SNP association analysis of reproduction traits in the Finnish Landrace pig breed. Genet. Sel. Evol. 43, 42.

Vanden Berghe, W., Vermeulen, L., De Wilde, G., De Bosscher, K., Boone, E., Haegeman, G.,2000. Signal transduction by tumor necrosis factor and gene regulation of the inflammatory cytokine interleukin-6. Biochem. Pharmacol. 60, 1185-1195.

Yang, L., Fu, J., Fu, Y., Wang, A., 2011. Association analysis between a polymorphism in the 5ˊ-regulatory region of the IL-6 gene and litter size in pigs. J. Anim. Sci. Biotech. 2, 187-191.

Yoo, I., Han, J., Kim, M., Jang, H., Sa, S., Choi, S.H., Ka, H., 2017. Expression and regulation of interleukin 6 and its receptor at the maternal-conceptus interface during pregnancy in pigs. Theriogenology 96, 85-91.

Zhang, Q., Huang, R., Ma, X., Jiang, N., Zhou, W., Gao, C., Zhao, M., Niu, P., Zhang, Z., Li,Q., Zhou, J., Li, P., 2019. Association of rs339939442 in the AHR gene with litter size are inconsistent among Chinese indigenous pigs and western commercial pigs.Animals 10, 11.