Gene expression formulas

$G$ = genome (or region) length in bp and $\ell$ = average Okazaki fragment length in nt. Every base pair is copied by exactly one fork, and each fork makes one strand continuously and the other discontinuously. So the total lagging-strand DNA equals $G$ nt, whatever the number of origins. Primer lengths and end effects at origins and termini are ignored.

4 bases in 3 positions give 64 codons: 61 sense codons (including AUG) and 3 stop codons (UAA, UAG, UGA).

$L_{\mathrm{ORF}}$ = nucleotides from the first base of the start codon to the last base of the stop codon, inclusive. $N_{\mathrm{aa}}$ = number of amino acids in the primary translation product, including the initiator Met. The +1 is the stop codon, which is not translated. If the initiator Met is removed after translation, add it back: a mature chain of $n$ residues gives $N_{\mathrm{aa}}=n+1$. Any signal peptide or propeptide that is cleaved off must be added back in the same way.