Two-cell and four-cell stage embryos derived from IVF and SCNT were collected at 24 and 48 hpi or hpa, washed twice in 0.05% BSA in PBS, and flash-frozen in liquid nitrogen. Ten embryos were pooled as a single sample. After thawing, polyadenylated RNAs were reverse transcribed and amplified, using SMART-Seq HT kits (R400748, Takara Bio, Shiga, Japan). Library preparation and sequencing were performed using a SMART-Seq HT kits (R400748, Takara Bio, Shiga, Japan).