Insertion related size polymorphisms of MtPH-A6-3 elements. A. Long PCR amplification of the region encompassing the MtPH-A6-3-IIa insertion site, B. PCR amplification of the region encompassing the MtPH-A6-3-VI insertion site, C. PCR amplification of the region encompassing the MtPH-A6-3-XVI insertion site. Lanes: M – 1 kB ladder (Fermentas), 1 – Jemalong A17, 2 – L163, 3 – L174, 4 – L368, 5 – L530, 6 – L544, 7 – L651, 8 – L734, 9 – negative control. Fragments representing occupied and unoccupied sites are marked by red and green arrows, respectively. Numbers in red indicate the expected length of products representing occupied sites, predicted from the original sequence.