Distribution of polytropic MLV-related proviruses in wild mice. Analysis of PvuII-digested mouse DNAs was performed by hybridization of the DNA in dried agarose gels with the P-I-specific oligonucleotide probe (Pltr) (A), the P-II-specific oligonucleotide probe (Mltr) (B), the P-IV-specific oligonucleotide probe (KT-58) (C), and the P-V-specific oligonucleotide probe (KT-76) (D). (A and B) Lanes: a, C57BL/6J; b, CASA/Rk (M. m. castaneus); c, SF/CamEi (M. musculus); d, PERA/Rk (M. musculus); e, PERC/Ei (M. musculus) (m.mus.); f, SPRET/Ei (M. spretus) (m.spr.); g, PANCEVO/Ei (M. spicelegus); h, Halbturn (M. spicelegus) (m.spi.); i, M. cervicolor (m.cer.); j, M. caroli (m.car.); k, M. cookii (m.coo.). (C and D) a, CZECH II/Ei (M. m. musculus); b, ZALENDE/Ei (M. m. domesticus) (m.mus.); c, SPRET/Ei (M. spretus) (m.spr.); d, PANCEVO/Ei (M. spicelegus); e, Halbturn (M. spicelegus) (m.spi.); f, M. cervicolor (m.cer.); g, M. caroli (m.car.); h, M. cookii (m.coo.). The approximate positions of molecular markers are also shown.