in addition a process is described for determining sequence modifications that promote stabilisation and translational efficiency of modified mrna of the invention application_number US 201615005808 A description the following examples describe the invention in more detail and in no way are to be construed as restricting the scope thereof as an exemplary embodiment of the process for determining the sequence of a modified mrna according to the invention a computer program was established that modifies the nucleotide sequence of an arbitrary mrna in such a way as to maximise the g c content of the nucleic acid and maximise the presence of codons recognized by abundant trnas present in a particular cell s the computer program is based on an understanding of the genetic code and exploits the degenerative nature of the genetic code by this means a modified mrna having desirable properties is obtained wherein the amino acid sequence encoded by the modified mrna is identical to that of the unmodified mrna sequence alternatively the invention may encompass alterations in either the g c content or codon usage of an mrna to produce a modified mrna the source code in visual basic 6 0 program development environment employed microsoft visual studio enterprise 6 0 with servicepack 3 is given in the appendix i an rna construct with a sequence of the lac z gene from e coli optimised with regard to stabilisation and translational efficiency was produced with the aid of the computer program of example 1 a g c content of 69 compared to the wild type.