Human T-lymphotropic virus type I tax polymorphisms in a transmission cohort: no association between sequence variation and disease manifestations.
OBJECTIVE
To determine whether a unique human T-lymphotropic virus type I (HTLV-I) transmission cohort containing multiple disease manifestations could be used to establish a relationship between tax gene sequence and HTLV disease expression.


METHODS
DNA was extracted from the peripheral blood mononuclear cells (PBMC) of the HTLV-infected persons in the cohort. A 1.1-kb fragment of tax was amplified by polymerase chain reaction (PCR) and cloned. Six to 12 individual clones were sequenced per person.


RESULTS
Comparison to a reference ATK strain showed numerous differences; however, consensus tax sequences from all persons within the transmission cohort were identical. Intraperson variation was 0.1% to 0.3%. Tax sequences from the index case did not differ from those obtained from a transfusion recipient who developed tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). Tax sequences from the same index case did not differ from sequences obtained from the asymptomatic or ATL phases of a second recipient.


CONCLUSIONS
In this cohort there did not appear to be tax genotypes associated with specific disease manifestations of HTLV infection.
Sambor
A M
AM
Henry M. Jackson Foundation, Rockville, Maryland, USA.
Pombo de Oliveira
M S
MS
Farhadi
A
A
Carr
J K
JK
Carvalho
S M
SM
Blattner
W A
WA
Kim
J H
JH
D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D016356:Gene Products, tax / Q000235:genetics*; D015490:HTLV-I Infections / Q000235:genetics* / Q000635:transmission; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA
D016356:Gene Products, tax