Table 4.

Mutational analysis.

Set	Average (SD)	P	Average (SD)	P	Average (SD)	P
A. dN/dS substitution analysis
GenBank	0.49 (0.21)
Cortex	0.32 (0.12)	.04
Liver	0.44 (0.18)	.39
Plasma	0.39 (0.16)	.12

B. Nucleotide mutational frequency analysis	Nucleotide		Amino acid
GenBank	20.55 (6.88)		6.32 (2.46)
Cortex	23.00 (5.40)	.38	5.83 (2.22)	.62
Liver	20.08 (4.33)	.814	5.91 (2.31)	.57
Plasma	20.51 (4.42)	.84	5.90 (2.42)	.59

C. Mutational frequency analysis	Very rare		Rare		Common
Nucleotide
GenBank	1.78 (2.70)		4.68 (2.94)		14.08 (5.35)
Cortex	3.00 (2.96)	.27	4.66 (1.36)	.98	15.33 (3.72)	.56
Liver	2.00 (2.21)	.78	4.58 (2.35)	.90	13.50 (4.52)	.70
Plasma	1.78 (2.54)	.81	4.68 (1.85)	.58	14.05 (3.72)	.50
Amino acid
GenBank	1.10 (1.55)		1.46 (1.57)		3.75 (1.88)
Cortex	1.00 (1.26)	.87	1.00 (0.63)	.47	3.83 (1.72)	.92
Liver	1.00 (0.85)	.81	1.41 (1.37)	.91	3.50 (1.56)	.64
Plasma	0.90 (1.10)	.68	1.40 (1.43)	.89	3.60 (1.71)	.80

D. BLOSUM score substitution analysis	Very rare (BLOSUM < 0)		Rare (BLOSUM = 0)		Common (BLOSUM > 0)
GenBank	1.63 (1.35)		2.25 (1.43)		2.56 (1.48)
Cortex	2.00 (1.67)	.50	1.83 (1.32)	.48	2.00 (1.54)	.35
Liver	1.83 (1.46)	.60	2.09 (1.57)	.71	2.09 (1.44)	.29
Plasma	1.60 (1.26)	.94	2.10 (1.52)	.74	2.20 (1.54)	.43

NOTE. P values are for the comparison with GenBank sequences. Boldface indicates a statistically significant difference. d_N/d_S, ratio of nonsynonymous to synonymous substitutions.