Skip to main content


HLA-G 14 bp insertion/deletion polymorphism is not associated to proviral load levels and presence of HAM/TSP in Peruvian HTLV-1 infected individuals


High HTLV-1 proviral load (PVL) has been associated with HAM/TSP disease in HTLV-1-infected individuals. Human leukocyte antigen (HLA) complex plays an important role in the immune response against virus-infected cells. One mechanism involves HLA-G binding to KIR2DL4 and modulates the activities of Natural Killer and CD8+ T cells. The 14-bp insertion/deletion in the 3’UTR exon 8 of HLA-G affects the HLA-G-mRNA-stability and therefore the HLA-G-protein levels. We analyzed the distribution of the 14-bp ins/del polymorphism among HTLV-1-infected individuals to evaluate its effect both on PVL and HAM/TSP.

Subjects and methods

394 unrelated HTLV-1-infected Peruvian individuals were included in this analysis (254 asymptomatic carriers [AC] and, 140 HAM/TSP). HLA-G 14-bp ins/del and KIR2DL4 were genotyped with PCR specific primers. PVL was determined by real-time quantitative PCR using human the endogenous retrovirus 3 as reference gene. Associations of KIR-HLA-G ins/del with PVL or HAM/TSP were evaluated through multivariate logistic and linear regression analysis using R-software.

Results and conclusions

KIR2DL4 was observed in all the individuals evaluated. The predominant genotype was +14-bp/-14-bp, both in AC (50.8%) and HAM/TSP (50.7%, P>0.05). HLA-G 14-bp ins/del showed no effect on PVL (P>0.05), nor with the presence of HAM/TSP in comparison to AC (P>0.05). This finding does not agree with the trend of high PVL observed for the -14-bp/-14-bp genotype, compared to +14-bp/-14-bp, +14-bp/+14-bp genotypes, in a Brazilian population. Our results stress the importance of replication studies in independent populations to demonstrate the association of host genetic factors with PVL or disease outcome in HTLV-I-infected subjects.

Author information

Correspondence to Sandra Morales.

Rights and permissions

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and Permissions

About this article


  • Natural Killer
  • Human Leukocyte Antigen
  • Load Level
  • Replication Study
  • Asymptomatic Carrier