This can be useful for the smaller scale of regenerative endodontics, where demand leads to the elaboration of critical factors important for pulpal innervation such as brain-derived neurotrophic factor (BDNF), up to the larger more vital scale of treating neurodegenerative diseases such as Alzheimer's and Parkinson's diseases (de Almeida et al., 2014). The gene discussed is BDNF; the disease is Parkinson disease.