Transforming activity of DNA fragments from normal human lymphocytes results from spontaneous activation of a c-Ha-ras1 gene.
An activated human Ha-ras gene was present in a secondary NIH 3T3 transformant isolated after serial transfection of originally low-molecular-weight DNA fragments from normal human cells. This gene appeared to have acquired its transforming properties by a spontaneous mutation in codon 12 by substitution of a deoxythymidine residue for a deoxyguanosine residue. DNA rearrangements in the flanking sequences of the transferred Ha-ras gene were not involved in the activation of the protooncogene.
D000818:Animals; D002471:Cell Transformation, Neoplastic; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics*; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism*; D051379:Mice; D009857:Oncogenes; D011519:Proto-Oncogenes; D014162:Transfection
D004247:DNA