Analysis of SSH-MOS subtraction efficiency. A) Cclap-ps male-specific transcript expression profile at early embryonic stages: first lane= DNA marker, 1=unfertilized eggs; 2=XX/XY 0-0.5 hour AEL embryos; 3=XX/XY 0.5-3 hours AEL embryos; 4= XX/XY 3-24 hours AEL embryos; 5=XX-only 0-0.5 hour AEL embryos; 6=XX-only 0.5-3 hours AEL embryos; 7= XX-only 3-24 hours AEL embryos. Negative control not shown. B) last lane=DNA marker, Cclap-ps transcript expression profile at adult stages: 1=XY adult males; 2=XX adult females; 3=negative control. C) first lane= DNA marker, The subtracted SSH and subtracted SSH-MOS secondary PCR products were amplified using primers for Y-linked Cclap-ps transcript. Aliquots of the samples were analyzed by gel electrophoresis after 18, 23, 28, and 33 cycles of PCR amplification.