Bovine leukemia virus tax gene/Tax protein polymorphism and its relation to Enzootic Bovine Leukosis

Figures & data

Table 1. The occurrence of tax protein variants in each subgroup of cows: BLV+ I, BLV+ I/II and BLV+ II are BLV- positive subgroups of animals

Tax alleles and Tax protein variants		The occurrence of Tax protein variants in each cow (in absolute numbers of 5–6 clones investigated) by subgroups
		BLV+ I						BLV+ I/II							BLV+ II
		1	2	3	4	14	15	16	13	5	6	9	10	11	8	7	12
tax	Tax
b, c, d, f	A	6	5	5	4	6	5
e	H				1
h	D														4
i	C														1
g	E															5
k	F																5
a, l	B							5	6	5	5	5	5	4
j	G													1

Table 2. Unpaired t-test results for groups and subgroups of cows. The two-tailed P values with a 95% confidence interval. WBC RI (the WBC reference interval) has been measured in WBC/µL. BLV -, BLV +, BLV+ I, BLV+ I/II, and BLV+ II areas in Table 1 and Figure 1. BLV- and BLV + status has been determined by both serology (AGID) for BLV antibody, and PCR detection of proviral BLV DNA

BLV – (N = 26) WBC RI is 5,906 ― 16,609
P ≤ 0.0001 This difference is considered to be extremely statistically significant.	BLV + (N = 16) WBC RI is 4,710 ― 29,322
	P = 0.1650 This difference is considered to be not statistically significant.	II BLV + (N = 3) WBC RI is 10,140 ― 35,146
	P = 0.5195 This difference is considered to be not statistically significant.	P = 0.3797 This difference is considered to be not statistically significant.	I/II BLV + (N = 7) WBC RI is 7,097 ― 30,540
P = 0.4768 This difference is considered to be not statistically significant.	P = 0.0730 This difference is considered to be not quite statistically significant.	P = 0.0054 This difference is considered to be very statistically significant.	P = 0.0223 This difference is considered to be statistically significant.	I BLV + (N = 6) WBC RI is 8,009 ― 16,191

Figure 1. ANOVA test results for BLV-negative (BLV-), BLV-positive (BLV+) groups, I-st BLV-positive (BLV+ I), I/II-nd BLV-positive (BLV+ I/II) and II-nd BLV-positive (BLV+ II) subgroups of cows. The number of WBCs (y × 10³ cells/μL) is on the y-axis. BLV- and

BLV+ status of these groups was determined by both serology (AGID) for BLV antibody, and PCR detection of proviral BLV DNA.

Table 3. Tax protein sequences have been used for the alignment (Figure 2) and the phylogenetic analysis (Figure 3). PL, T, AL, EBL*, EBL areas in Figure 2,3

GeneBank numbers of Tax sequences
different	the same	Genotypes	Manifestations of the disease	References
BAX04241.1		G1	EBL	[20]
CCJ67619.1		G1	T	[21]
BAX04259.1		G1	EBL	[20]
BAR47041.1	BAR47041.1	G?	T	[21]
	CCJ67631.1	G?	T	[21]
	CCJ67625.1	G?	T	[21]
	BAX04286.1	G1	EBL	[20]
	BAX04268.1	G1	EBL	[20]
	BAX04223.1	G1	EBL	[20]
	BAX04160.1	G1	AL	[20]
	BAX04151.1	G1	AL	[20]
	BAX04124.1	G1	AL	[20]
	BAX04115.1	G1	AL	[20]
	BAX04106.1	G1	AL	[20]
	BAX04088.1	G1	EBL*	[20]
	BAX04061.1	G1	AL	[20]
	BAX04052.1	G1	EBL*	[20]
	BAX47046.1	G?	T	[30]
BAP46819.1		G?	T
BAX04169.1	BAX04169.1	G1	AL	[20]
	BAX04079.1	G1	AL	[20]
BAX04142.1		G1	AL	[20]
BAX04205.1	BAX04205.1	G1	EBL	[20]
	BAX04196.1	G1	EBL	[20]
	BAX04187.1	G1	EBL	[20]
BAX04277.1		G1	EBL	[20]
BAX04178.1		G1	EBL	[20]
BAU59290.1		G?	T	[22]
BAX04250.1	BAX04250.1	G1	EBL	[20]
	BAX04232.1	G1	EBL	[20]
	BAX04214.1	G1	EBL	[20]
BAX04133.1	BAX04133.1	G1	AL	[20]
	BAX04097.1	G1	AL	[20]
	BAX04070.1	G1	AL	[20]
AUV64408.1		G10	AL	[4]
ACR15161.1		G2	AL	[7,23]
AAF97920.1		G2	PL	[24,25]
AUV64420.1		G6	AL	[4]
AUV64414.1		G10	AL	[4]
AUV64426.1		G6	AL	[4]
AUV64438.1		G10	AL	[4]
AUV64432.1		G10	AL	[4]

Figure 2. Alignment of Tax amino acid sequences./ – \― structural domains, + ― phosphorylation sites. BLV+ I, BLV+ I/II and BLV+ II areas in Figure 1. PL ― Persistent Lymphocytosis, T ― tumor (B-cell leukemia/lymphoma), AL ― aleukemic (asymptomatic, healthy or non-EBL), EBL* ― the disease has developed during the observation period (AL → EBL), EBL ― Enzootic Bovine Leukosis (PL or T are unknown) (Table 3)

Figure 3. Tax primary protein sequence evolutionary analysis by Maximum Likelihood method. The percentage of trees in which the associated sequences clustered together is shown next to the branches. BLV+ I, BLV+ I/II, BLV+ II, PL, T, AL, EBL*, EBL areas in Figure 1, 2. G1, G2, G6, and G10 ― BLV genotypes, based on env genes and complete proviral genomic sequences, for which references are given in Table 3. Square brackets indicate the sequence numbers that represent groups of identical ones (Table 3)

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