qPCR analysis of GFP-positive and GFP-negative cell populations harvested via FACS at day 3 of suspension culture in EBs generated from 300×300×120 µm microwells. Fold difference is compared to the GFP-negative population. GFP-positive fractions contained higher expression of Wnt target genes AXIN2, FST, FZD7, and SLUG, primitive streak markers GSC and MIXL1, mesoderm marker T, WNT3A, cardiac transcription factor NKX2-5, and cardiac progenitor marker ISL1 (* indicates P<0.05, ** indicates P<0.005, *** indicates P<0.0005 compared to the GFP-negative population).