BDNF and juvenile Huntington disease: Disruption of cAMP response element-binding protein (CREB) affects the transcription of brain-derived neurotrophic factor (BDNF), leading to the loss of normal function of the specific protein Huntington in Huntington’s disease, where a reduction in cGMP is also observed in the context of highly expanded PolyQ proteins (Myeku and Duff, 2018).