N. Bouck, N. Beales, T. Shenk, P. Berg, and G. Di-mayorca, New region of the simian virus 40 genome required for efficient viral transformation, Proc. nat. Acad. Sci. (Wash.), vol.75, pp.1274-1278, 1978.

A. R. Buchman, L. Burnett, and P. Berg, The SV, nucleotide sequence, DNA tumor viruses, pp.799-841, 1982.

C. De-fromentel, C. Nardeux, P. C. Soussi, T. Lavialle, C. Estrade et al., Epithelial HBL-100 cell line derived from milk of an apparently healthy woman harbours SV, genetic information, Exp. Cell Res, vol.160, pp.83-94, 1985.

L. Daya-grosjean, M. R. James, C. Drougard, and A. Sarasin, An immortalized Xeroderma pigmentosum, group C, cell line which replicates SV, shuttle vectors, Mutation Res, vol.183, pp.185-196, 1987.

J. Feunten, G. Carmichael, J. C. Nicolas, M. Kress, J. Feunten et al., Mutant carrying deletions in the two simian virus 40 early genes, Proc. nat. Acad. Sci. (Wash.), vol.40, p.44554459, 1978.

A. M. Frischauf, H. Lehrach, A. Poustka, and N. Murray, Lambda replacement vectors carrying polylinker sequences, J . mol. Biol, vol.170, pp.827-842, 1983.

E. V. Gaffney, A cell line (HBL-100) established from human breast milk, Cell Tissue Res, vol.227, pp.563-568, 1982.

W. R. Gish and M. R. Botchan, Simian virus 40-transformed human cells that express large T-antigens defective for viral DNA replication, J . Virol, vol.61, pp.2864-2876, 1987.

D. Hanahan, Studies on transformation of Escherichia coli with plasmids, J. mol. Biol, vol.166, pp.557-580, 1983.

M. Hattori and Y. Sakaki, Dideoxy sequencing method using denatured plasmid templates, Anal. Biochem, vol.152, pp.232-238, 1986.

S. Henikoff, Unidirectional digestion with exonuclease 111 creates targeted breakpoints for DNA sequencing, Gene, vol.28, pp.351-359, 1984.

B. Hirt, Selective extraction of polyoma DNA from infected mouse cell cultures, J mol. Biol, vol.26, pp.365-369, 1967.

J. Karn, S. Brenner, L. Barnett, and G. Cesareni, Novel bacteriophage cloning vector, Proc. nar. Acad. Sci (Wash.), vol.77, pp.5172-5176, 1980.

G. Kimura and R. Dulbecco, Isolation and characterization of temperature-sensitive mutants of Simian virus 40, Virology, vol.49, p.394403, 1972.

A. Macieira-coelho and B. Azzarone, Aging of human fibroblasts is a succession of subtle changes in the cell cycle and has a final short stage with abrupt events, Exp. Cell Res, vol.141, pp.325-332, 1982.

I. Macpherson and L. Montagnier, Agar suspension culture for the, pp.625-634, 1981.

, Caron de Fromentel et ul., 1 9 8 5 t m i g h t have been infected in the mammary gland of the milk donor by an SV, virus originally contaminating a polio virus vaccine. LNCES selective assay of cells transformed by polyoma virus, progenitor cells of which-as already suggested, vol.23, pp.291-294, 1964.

T. Maniatis, E. F. Fritsch, and J. Sambrook, Molecular cloning: a laboratory manual, 1982.

M. M. Manos and Y. Gluzman, Simian virus 40 large T-antigen point mutants that are defective in viral DNA replication but competent in oncogenic transformation, Mol. cell. Biol, vol.4, pp.1125-1126, 1984.

M. M. Manos and Y. Gluzman, Genetic and biochemical analysis of transformation-competent, replication-defective simian virus 40 large Tantigen mutants, J. Virol, vol.53, pp.120-127, 1985.

S. Manteuil, J. Pagbs, D. Stbhelin, and M. Girard, Replication of simian virus 40 deoxyribonucleic acid: analysis of the one step growth cycle, J. Virol, vol.11, pp.98-106, 1973.

F. Marlhens, C. Saint-ruf, P. Nardeux, C. Lavialle, D. Broutyboub et al., Karyotype evolution of the human HBL-100 cell line and mapping of the integration site of SV, DNA. Ann. GCnCr, vol.31, pp.81-86, 1988.

J. Messing and J. Vieira, A new pair of MI3 vectors for selecting either DNA strand of double digest restriction fragments, Gene, vol.19, pp.269-276, 1982.

F. Pecceu, A. Komly, M. Gardes, and J. Feunten, Properties of simian virus 40 mutants lacking the Asp,-Glu-Asp stretch at the carboxylterminus of large T-antigen, Virology, vol.160, p.485488, 1987.

J. M. Pipas, K. W. Peden, and D. Nathans, Mutational analysis of simian virus 40 T-antigen: isolation and characterization of mutants with deletions in the T-antigen gene, Mol. cell. Biol, vol.3, pp.203-214, 1983.

F. P. Polanowski, E. V. Gaffney, and R. E. Burke, HBL-100, a cell line established from human breast milk, In Vitro, vol.12, p.328, 1976.

F. Sanger, S. Nicklen, and A. R. Coulson, DNA sequencing with chain-terminating inhibitors, Proc. nat. Acad. Sci. (Wash.), vol.74, pp.5463-5467, 1977.

A. Sarasin, C. F. Menck, J. , and M. R. , Shuttle vector-host systems for analysis of mutagenesis in mammalian cells. Phorobiochem. Photobiophys, pp.343-351, 1987.

T. E. Shenk, J. Carbon, and P. Berg, Construction and analysis of viable deletion mutants of simian virus 40, J. Virol, vol.18, pp.664-671, 1976.

M. L. Sleigh, W. C. Topp, R. Hanich, and J. F. Sambrook, Mutants of SV, with an altered small t protein are reduced in their ability to transform cells, Cell, vol.14, pp.79-88, 1978.

R. Wicker and S. Avrameas, Localization of virus antigens by enzymelabelled antibodies, J. gen. Virol, vol.4, p.465471, 1969.

M. Wigler, A. Pellicer, S. Silverstein, A. , and R. , Biochemical transfer of single-copy eucaryotic genes using total cellular DNA as donor, Cell, vol.14, pp.725-731, 1978.

M. J. Zoller and M. Smith, Oligonucleotide-directed mutagenesis of DNA fragments cloned into M13 vectors, Methods in enzymology, vol.100, pp.468-500, 1983.