Fig. 7. Southern blot analysis of RT-PCR amplified products of Hegfl, Erbb1 and Erbb4 in preimplantation embryos and day-4 uteri of hamsters. Lanes 1-5, one-cell, two-cell, four-cell, eight-cell/morula and blastocyst stages, respectively; lane 6, day 4 uterus; lane 7, day 4 uterine RNA without RT; lane 8, primer control. These experiments were performed twice with similar results.