INS and obesity due to melanocortin 4 receptor deficiency: Msr have also been implicated with neurodegenerative diseases such as Alzheimer's and Parkinson's disease (Glaser et al, 2005), auditory function and hearing loss (Kwon et al, 2014; Kim et al, 2016), visual deterioration (Pascual et al, 2010), and obesity (Styskal et al, 2013), and insulin resistance (Kaneto et al, 2010).