TABLE 2.

Observed and expected distributions of mono-, di-, and trinucleotide repeats in the HCMV AD169 genome^a

No. of repeat units	Mononucleotides			Dinucleotides			Trinucleotides
	No. observed	No. expected	Deviation	No. observed	No. expected	Deviation	No. observed	No. expected	Deviation
2	31,203	32,112 ± 30.8	−	8,209	7,394 ± 13.2	+	4,307	2,518 ± 8.8	+
3	7,152	8,241 ± 18.9	−	644	486 ± 5.8	+	275	43.7 ± 1.3	+
4	2021	2,153 ± 7.3	−	70	33 ± 1.1	+	27	1.15 ± 0.3	+
5	659	572 ± 5.3	+	5	1.9 ± 0.4	+	2
6	199	154 ± 2.3	+
7	69	42 ± 1.6	+
8	24	11 ± 0.6	+
9	27	3 ± 0.4	+
10	17
11	2
12	3
13	2

^aTarget repeats for study are in boldface. The expected number of repeats is the mean of 20 genomes with standard error. All observed values were significantly different from expectation (in all cases, P ≤ 0.001). “Deviation” indicates whether the observed number was significantly more (+) or less (−) than expectation. Tetra-, penta-, and hexanucleotide repeats are extremely rare and match random expectations and are therefore not shown.