Identification and cloning of endogenous retroviral sequences present in human DNA.

Abstract
Using nonstringent annealing conditions and a 2.75 (kb) segment of cloned African green monkey DNA that specifically hybridizes to the proviruses of AKR ecotropic murine leukemia virus (MuLV) and baboon endogenous virus (BaEV) as a probe, related sequences were detected in 3 different preparations of human brain DNA fragments. The blot-hybridization pattern obtained with cleaved human DNA was similar to that previously reported for the interaction of MuLV c[complementary]DNA and cleaved mouse DNA and suggested the presence of numerous copies of retrovirus-related sequences in the human genome. The labeled 2.75 kb fragment derived from cloned moneky DNA was used to screen a human DNA library in phage Charon 4A. One clone obtained hybridized to 3 contiguous MuLV-and BaEV-reactive fragments of the cloned monkey DNA and to multiple fagments of human DNA including a prominent 1.0 kb EcoRI fragment also present in the clone.