Ancient HTLV type 1 provirus DNA of Andean mummy

The worldwide geographic and ethnic clustering of patients with diseases re lated to human T cell lymphotropic virus type 1 (HTLV-1) may be explained b y the natural history of HTLV-1 infection. The genetic characteristics of i ndigenous people in the Andes are similar to those of the Japanese, and HTL V-1 is generally detected in both groups. To clarify the common origin of H TLV-1 in Asia and the Andes, we analyzed HTLV-1 provirus DNA from Andean mu mmies about 1500 years old. Two of 104 mummy bone marrow specimens yielded a band of human beta -globin gene DNA 110 base pairs in length, and one of these two produced bands of HTLV-1-pX (open reading frame encoding p(40x), p(27x)) and HTLV-1-LTR (long terminal repeat) gene DNA 159 base pairs and 1 57 base pairs in length, respectively. The nucleotide sequences of ancient HTLV-1-pX and HTLV-1-LTR clones isolated from mummy bone marrow were simila r to those in contemporary Andeans and Japanese, although there was microhe terogeneity in the sequences of some mummy DNA clones. This result provides evidence that HTLV-1 was carried with ancient Mongoloids to the Andes befo re the Colonial era. Analysis of ancient HTLV-1 sequences could be a useful tool for studying the history of human retroviral infection as well as hum an prehistoric migration.