On the other hand, such control groups do not account for the impact of chronic inflammatory responses that control HTLV-1 burden in the peripheral blood, which rise serum baseline levels of chemokines in infected individuals, as demonstrated by higher serum levels of CCL2 and CXCL8 in HTLV-1 infected individuals in general, and of CXCL10 in HAM/TSP patients. This evidence concerns the gene CCL2 and tropical spastic paraparesis.