Fixation of the transposable elements on the neo-Y chromosome. Lanes 1 to 12 show the PCR product of the 12 different D. miranda strains investigated, using male genomic DNA. Lane 13 shows one representative female (note: no female amplified a PCR product) and lane 14 shows a size standard (500-bp ladder). (A) worf, 1.9-kb PCR product. (B) spock, 1.9-kb product. (C) TRIM, 890-bp product. (D) TRAM, 780 bp-product