Table 2. Comparison of the prevalence of deletion, mutation rates, and substitutions in the preS1, preS2, S and overlapped P regions between the occult subjects and HBV carriers in this study.

Regions	Characteristics		Occult (n = 41) (%)	Carrier (n = 40) (%)	P-value
PreS1	Total of Deletion		15 (36.6)	4 (10.0)	0.008
	Premature stop		3 (7.3)	0 (0)	NS
	Mutations	Hepatocyte binding site (aa 21–47)	11 (26.8)	5 (12.5)	NS
		Deletion of Start codon	11 (26.8)	3 (7.5)	0.037
		S17A	5 (12.2)	0 (0)	0.023
		P32L	5 (12.2)	0 (0)	0.023
		W43L/R	6 (14.6)	0 (0)	0.012
		H51P/R	6 (14.6)	1 (2.5)	0.052
		I84T/M	8 (19.5)	1 (2.5)	0.015
	Mutation rates per hundred of amino acids		2.0/100	0.6/100	<0.001
PreS2	Total of Deletion		7 (17.1)	1 (2.5)	0.028
	Premature stop		5 (12.2)	1 (2.5)	NS
	Mutations	W3R/Stop	5 (12.2)	0 (0)	0.012
		S5A	4 (9.8)	0 (0)	0.043
	Mutation rates per hundred of amino acids		1.6/100	0.5/100	<0.001
Small Surface	Premature stop		8 (19.5)	0 (0)	0.003
	Mutations	I/T126N/S	11 (26.8)	3 (7.5)	0.037
		W182L/Stop	15 (36.6)	0 (0)	0.001
	Mutations of the “a” Determinant		15 (36.6)	5 (12.5)	0.019
	Mutation rates per hundred of amino acids		1.4/100	0.6/100	<0.001
Overlapped Polymerase	Total of Deletion		22 (53.7)	5 (12.5)	<0.001
	Premature stop		8 (19.5)	2 (5.0)	0.047
	Mutations in the YMDD region		4 (9.8)	1 (2.5)	NS
	Mutation rates per hundred of amino acids		0.7/100	0.4/100	<0.001
PreS1+ PreS2+ Small Surface	Premature stop		16 (39.0)	1 (2.5)	<0.001

NS: not significant.