Levels of genetic differentiation were measured by the fixation index FST, based on nucleotide frequency differences [64].
Frequency Analysis of Sequence Data (FASD[8]), a program that predicts taxonomy based on nucleotide frequency and order rather than sequence alignment, detected new sequences representing the S1, S2, S3 and S4 segments (Figure 1) that comprised an additional 11.8% of the final viral genome assembly.
The original values of the downloaded PWMs were based on nucleotide frequencies and therefore more similar to Positional Frequency Matrices.
For each miRNA separately we ran MEME (Bailey and Elkan, 1994 ), with the settings: -dna -mod zoops -maxw 7 -nmotifs 1, using the default 0-order Markov model based on nucleotide frequencies in the training set as the background model.
Based on nucleotide frequencies of sequences surrounding mORFs, it is predicted that the Drosophila optimal consensus sequence is CAaa AUGg [ 2, 30], but no functional experiments have been conducted in insects to validate the strength of this initation context.
Similar to the transition probabilities above, only a small fraction of the possible transitions are allowed: states where the second nucleotides in the two alleles are A and G, for example, can only transition to states where the first nucleotides are A and G, and the transition probabilities in such cases are based on nucleotide frequencies.
Methods to do such removals include ORF detection [ 1, 9, 16, 25], BLAST to identify homologs of protein coding genes [ 25], domain based searches such as Pfam [ 9, 25], and predictions of coding potential based on nucleotide substitution frequencies given sequences from multiple species.
Replacing the Ribosum-like [ 15] definition of σ and τ in LocARNA, we suggest to utilize log-odd scores based on nucleotide (and nucleotide pair) frequencies in this multiple alignment.
Observed frequencies were divided by the theoretical frequency based on nucleotide biases that were estimated from the nucleotide composition of the genome.
Finally, we tested if the pmt allele frequency distribution, based on nucleotide diversity measures, deviated from neutrality in a tolerant and sensitive population.
This reaction is based on nucleotide complementarity [19].
