Table 1. Results from repeated measures ANOVA to test for significant effects of genetic background (line), age, and their interaction on crossover frequency in the two intervals assayed.

Chromosome	Source	df	SS	MS	F-Value	Prob > F
X	Line	4	1.34	0.34	10.25	< 0.001
	Residuals	305	9.96	0.033
	Maternal age	1	1.32	1.32	54.19	< 0.001
	Line × maternal age	4	0.66	0.17	6.78	< 0.001
	Residuals	1855	45.19	0.024
3R	Line	2	0.0011	0.00059	0.033	0.97
	Residuals	15	0.27	0.018
	Maternal age	1	0.046	0.046	2.93	0.097
	Line × maternal age	2	0.069	0.0035	0.22	0.80
	Residuals	33	0.52	0.016

df, degrees of freedom; SS, sum of squares; MS, mean square.