Question: A and B are linked. Analysis of a linked RFLP in two purebreeding lines, AABB and aabb, showed that the first was also homozygous for a long RFLP allele (RL), while the second was homozygous for a short allele (RS). The two lines were crossed to form an F1, which was then backcrossed to the aabb line. 1000 progeny were scored as follows:
3 AaBbSS
372 AaBbLS
103 AabbLS
23 AabbSS
5 aabbLS
364 aabbSS
21 aaBbLS
109 aaBbSS
Determine the distance between A and the polymorphic restriction site that is associated with the RFLP?