(E) A worked example of calculation of the F values. First the coverage of E2 to E3 link (CE2 − E3) is determined from level 1 unique regions (CE2u,1 − E3u,1), which is then subtracted from the coverage attained from the pseudo-unique E1 to E3 link (CE1u,2 − E3u,1) in order to calculate the true E1 − E3 coverage (CE1 − E3). In the forward direction, E1 and E2 become primary exons and in the reverse direction E3 is the primary exon and the corresponding F values are calculated as shown.