Table 2.

Error counts in sequences derived from NaOH-treated oligonucleotides

Observed nucleotide count (%; 95%CI)	Expected nucleotide (n)
	A (1320)	T (1140)	C (1200)	G (2820)	Possible 5 mC (600)
A	1314	0	1	4	0
	(99.2%; 98.7–99.6%)	(0.08%; 0.002, 0.31%)	(0.08%; 0.02–0.46%)	(0.18%; 0.06–0.36%)	(0.16%; 0.004, 0.61%)
T	0	1137	11	0	1
	(0.07%; 0.018, 0.27)	(99.8%; 99.8–99.9%)	(0.92%; 0.5–1.7%)	(0.03%; 0, 0.13%)	(0.33%; 0.04, 0.92%)
C	3	2	1182	7	599
	(0.3%; 0.08–0.7%)	(0.26%; 0.05–0.65%)	(98.5%; 97.6–99.1%)	(0.28%; 0.12–0.5%)	99.8%; 99.4–99.9%
G	3	1	6	2809	0
	(0.3%; 0.08–0.7%)	(0.2%; 0.02–0.48%)	(0.5%; 0.18–1.1%)	(99.6%; 99.3–99.8%)	(0.16%; 0.004, 0.61%)

Error counts were recorded from 60 single-stranded oligonucleotide molecules, excluding the 5′ overhang and primer-binding regions. For each molecule, we collected information from 22 adenines, 19 thymines, 20 unmethylated non-CpG cytosines, 47 guanines and 10 methylated, CpG cytosines. See Methods section and the legend of Table 1 for information on calculation of point estimates and their CIs.