TABLE 1.

Marker types on the current mapping interval and their QTL distributions in a backcross population

			Marker genotype		Frequency of QTL genotype
Group	Sample size	Frequency	j	j + 1	QQ	Qq	Distribution of
1	n1		+	+
2	n2		+	−
3	n3		−	+
4	n4		−	−

and , where , , and are the recombination frequencies between marker j and the QTL, between the QTL and marker j + 1, and between markers j and j + 1, respectively. “+” denotes homozygote for the marker genotype and “−” denotes heterozygote. and represent the distributions for the two QTL genotypes QQ and Qq, respectively.