Table 1. Ratios of different types of substitutions.

Type of substitution	Percentage transitions			Percentage transversions
	C/T		G/A	C/G	T/A		T/G		C/A
JSNP	34.80		35.20	10.20	4.60		7.30		7.60
CSNP map for chromosome 21a	–	70.00	–	–	–	30.00	–		–
SNP resource chromosome 22b	–	70.40	–	9.44	4.94		–	15.38	–
Celera PFPc	30.70		30.70	9.20	8.60		10.30		10.30

^aFrom table 2 in Deutsch et al. (8).

^bFrom table 3 in Dawson et al. (7).

^cFrom table 16 in Venter et al. (9).