## Figure 3.
Progressive expansion of RI genetic maps during inbreeding. The middle series of points
(red) that start at generation 2 shows the addition of map length - and the proportional
increase in the numbers of recombination breakpoints - relative to a standard one
meiotic generation F2 map. For example, at generation 7, approximately 2 map lengths
have been added to the initial map. By F24 the total RI map is almost precisely 4
times as long as a standard F2 map. This same addition characterizes other diallele
crosses that start near Hardy-Weinberg equilibrium, including advanced intercrosses.
A two-strain G8 advanced intercross with a 6000 cM map length would ultimately produce
a G8 RI set with map length of 6000 + 3 × 1400 cM = 10200 cM. The upper series of
points (blue) illustrate the accumulation in map length in a four-strain intercross
at Hardy-Weinberg equilibrium at generation 0. This cross will gain up to 3.75 map
equivalents. The lowest set of point is the inbreeding coefficient at each generation.
For a tabulation of these data and methods for calculating two- and four-strain expansion
values see
www.nervenet.org/papersBXN.html.
Williams |