[1] Vajta G. Somatic cell nuclear transfer in its first and sec-ond decades: successes, setbacks, paradoxes and perspectives. Reprod Biomed, 2007, 15(5): 582-590.[2] Lee GS, Kim HS, Hyun SH, Lee SH, Jeon HY, Nam DH, Jeong YW, Kim S, Kim JH, Han JY, Ahn C, Kang SK, Lee BC, Hwang WS. Production of transgenic cloned piglets from genetically transformed fetal fibroblasts selected by green fluorescent protein. Theriogenology, 2005, 63(4): 973-991.[3] Watanabe S, Iwamoto M, Suzuki SI, Fuchimoto D, Honma D, Nagai T, Hashimoto M, Yazaki S, Sato M, Onishi A. A novel method for the production of transgenic cloned pigs: electroporation-mediated gene transfer to non-cultured cells and subsequent selection with puromycin. Biol Reprod, 2005, 72(2): 309-315.[4] Lai LX, Kang JX, Li RF, Wang JD, Witt WT, Yong HY, Hao YH, Wax DM, Murphy CN, Rieke A, Samuel M, Linville ML, Korte SW, Evans RW, Starzl TE, Prather RS, Dai Y. Generation of cloned transgenic pigs rich in omega-3 fatty acids. Nat Biotechnol, 2006, 24(4): 435-436.[5] Li RF, Lai LX, Wax D, Hao YH, Murphy CN, Rieke A, Samuel M, Linville ML, Korte SW, Evans RW, Turk JR, Kang JX, Witt WT, Dai YF, Prather RS. Cloned transgenic swine via in vitro production and cryopreservation. Biol Reprod, 2006, 75(2): 226-230.[6] Vajta G, Zhang YH, Macháty Z. Somatic cell nuclear transfer in pigs: recent achievements and future possibilities. Reprod Fertil Dev, 2007, 19(2): 403-423.[7] Pratt SL, Sherrer ES, Reeves DE, Stice SL. Factors influ-encing the commercialisation of cloning in the pork in-dustry. Soc Reprod Fertil Suppl, 2006, 62(1): 303-315.[8] Kang YK, Koo DB, Park JS, Choi YH, Chung AS, Lee KK, Han YM. Aberrant methylation of donor genome in cloned bovine embryos. Nat Genet, 2001, 28(2): 173-177.[9] Kang YK, Yeo S, Kim SH, Koo DB, Park JS, Wee G, Han JS, Oh KB, Lee KK, Han YM. Precise recapitulation of methylation change in early cloned embryos. Mol Reprod Dev, 2003, 66(1): 32-37.[10] Turner BM. Histone acetylation and an epigenetic code. Bioessays, 2000, 22(9): 836-845.[11] Rice JC, Allis CD. Histone methylation versus histone acetylation: new insights into epigenetic regulation. Curr Opin Cell Biol, 2001, 13(3): 263-273.[12] Shogren-Knaak M, Ishii H, Sun JM, Pazin MJ, Davie JR, Peterson CL. Histone H4-K16 acetylation controls chromatin structure and protein interactions. Science, 2006, 311(5762): 844-847.[13] Li XP, Kato Y, Tsuji Y, Tsunoda Y. The effects of trichostatin A on mRNA expression of chromatin structure-, DNA methylation-, and development-related genes in cloned mouse blastocysts. Cloning Stem Cells, 2008, 10(1): 133-142.[14] Kishigami S, Mizutani E, Ohta H, Hikichi T, van Thuan N, Wakayama S, Bui HT, Wakayama T. Significant im-provement of mouse cloning technique by treatment with trichostatin A after somatic nuclear transfer. Biochem Biophys Res Commun, 2006, 340(1): 183-189.[15] Iager AE, Ragina NP, Ross PJ, Beyhan Z, Cunniff K, Rodriguez RM, Cibelli JB. Trichostatin A improves his-tone acetylation in bovine somatic cell nuclear transfer early embryos. Cloning Stem Cells, 2008, 10(3): 371-380.[16] Zhang YH, Li J, Villemoes K, Pedersen AM, Purup S, Vajta G. An epigenetic modifier results in improved in vitro blastocyst production after somatic cell nuclear transfer. Cloning Stem Cells, 2007, 9(3): 357-363.[17] Li J, Svarcova O, Villemoes K, Kragh PM, Schmidt M, Bøgh IB, Zhang Y, Du Y, Lin L, Purup S, Xue Q, Bolund L, Yang H, Maddox-Hyttel P, Vajta G. High in vitro development after somatic cell nuclear transfer and trichostatin A treatment of reconstructed porcine embryos. Theriogenology, 2008, 70(5): 800-808.[18] Kong QR, Wu ML, Huan YJ, Zhang L, Liu HY, Bou G, Luo YB, Mu YS, Liu ZH. Transgene expression is associated with |