Lack of genetic damage in mammalian cells after cryopreservation at -196 degrees C.

Mammalian tissue culture cells when cryopreserved according to standard procedures do not show gross chromosomal changes as evidenced by the formation of micronuclei. Cryoprotective agents used in this study included dimethyl sulfoxide (DMSO), glycerol and polyvinylpyrollidone (PVP) in combination with serum and using freezing and thawing rates normally employed in cryopreservation studies. In preliminary experiments, point mutations as evidenced by oubain resistance were not observed. These results are discussed in relation to previous studies indicating genetic stability after freezing and thawing.