  Neumann-Held argues that this conception provides the clearest basis for understanding how DNA sequences are “used in the processes of polypeptide production.” She points out that the process molecular gene concept allows for the inclusion of coding sequences in DNA, regulatory sequences in DNA and also entities not located in DNA, all of which are causally involved in the production of polypeptides. Neumann-Held's concept excludes transcription processes and coding regions of DNA that lead to functional RNA molecules that are not translated into polypeptides. Hence, according to her account, there are not process molecular genes for tRNA (transfer RNA), rRNA (ribosomal RNA) or snRNA (small nuclear RNA). This feature of Neumann-Held's definition does not match the textbook definition that she quotes to motivate her account (presented above). Furthermore, the exclusion of these coding regions does not track with recent discoveries about the important functions played by non-coding RNA molecules such as snRNAs. Her definition could easily be revised to accommodate these regions and processes. In any case, Neumann-Held believes using this concept in developmental genetics, rather than DNA-centered gene concepts, will help avoid the view that “genes are the most important explanatory factors in biology because of their unique causal powers” (Neumann-Held 2001, p. 80).