Grain colour in wheat is determined by three pairs of polygenes. Following the cross AABBCC (dark colour) x aabbcc (light colour), in $\mathrm{F}_2$ generation what proportion of the progeny is likely to resemble either parent?

Polygene results in quantitative inheritance. Quantitative inheritance is characterised by occurrence of intermediate forms between the parental type. There will be $7(1: 6: 15: 20: 15: 6: 1)$ phenotypes when three polygene pairs are involved. The total number of progeny would be 64 . Out of these sixty four only two will be likely to resemble either parents. Hence their proportion in $\mathrm{F}_2$ generation would be 3.12 i.e. less than five per cent.