[Transversions and transitions].

The investigation of 163 spontaneous point mutations of the human hemoglobin and the analysis of the genetic code make it possible to estimate the relative probability of transversions, which happens to be 0.30. From 23 possible nonsense mutations 15 are the transversions. Hence the genetic code provides the low probability of the mutational termination of the protein chain. The most dangerous are the mutations in the codon UGG (Trp).