Differences in Selective Profiles Between H. Sapiens and SARS-Cov-2 Genomes Confirm Double or Single Stranded DNA or RNA

Author(s): Carlos Y Valenzuela

Background: The debate between selective and neutral evolution is endless, even though the neutral theory of evolution cannot fully account for neutral evolution. I developed a method to study neutral evolution by the distance to neutrality (randomness) that the two bases of dinucleotides have between them. Method: 1) the sets of dinucleotides whose bases are separated by 0, 1, 2, …K sites were obtained from genomes. 2) The chi-squares tests of the distance to neutrality of the first base in relation to the second base were calculated for each set and dinucleotide. 3) This allows construct the matrix of significance (chi-squares values) vs separations (K) of the deviations from neutrality of dinucleotides. 4) From this matrix the selective profile (significance order, sign of selection and selection coefficient) were calculated and compared between parallel (Par) and antiparallel (a-Par) dinucleotides with their index dinucleotide. 5) The distances between the index-Par or Index-a-Par dinucleotides within the human chromosome 21 and SARS-CoV-2 were obtained and compared. Results: In HCh21, the Index and a-Par dinucleotides present almost equal selective profile, while the Par dinucleotides differ from the Index profiles. In SARS-CoV-2, a-Par and Par dinucleotides differ from the Index dinucleotides and differ one another. Conclusions: The almost equality of the selective profile between a-Par and the Index indicates that both strands of DNA of double stranded DNA (human) evolve together; this cannot occur in single stranded RNA (SARS-CoV-2 virus).