After treating with 45ug/mL boiled RNase A for 30 minutes, DNA was purified and concentrated using column purification. The DNA sample was run on 1% agarose, stained with SYBR Gold, and the gel piece containing DNA fragments less than 500bp was isolated and purified. DNA sample yield was measured using a Qubit fluorimeter. 50 base pair single ended sequencing library for embryo replicates B, C, D and L1 arrest X,Y,Z. 76 base pair single ended sequencing library for embryo replicate A and L1 arrest replicates W and V. Illumina HiSeq2500