 A second philosophical approach for conceptualizing the gene involved rethinking a single, unified gene concept that captured the molecular-developmental complexities. For example, Eva Neumann-Held (Neumann-Held 1999, 2001; Griffiths and Neumann-Held 1999) claimed that a “process molecular gene concept” (PMG) embraced the complicated developmental intricacies. On her unified view, the term “gene” referred to “the recurring process that leads to the temporally and spatially regulated expression of a particular polypeptide product” (Neumann-Held 1999). Returning to the case of cystic fibrosis, a PMG for an individual without the disease referred to one of a variety of transmembrane ion-channel templates along with all the epigenetic factors, i.e., nongenetic influences on gene expression, involved in the generation of the normal polypeptide product. And so cystic fibrosis arose when a particular stretch of the DNA sequence was missing from this process. (For another example of a gene-concept unifier, see Falk’s discussion of the gene as a DNA sequence that corresponded to a single norm of reaction for various molecular products based on varying epigenetic conditions (Falk 2001).)