A whole-exome sequencing study has identified rare variants and genes associated with intraocular pressure and glaucoma. However, it appears that similar studies have also been conducted on other conditions, including amyotrophic lateral sclerosis, Parkinson's disease, schizophrenia, opioid dependence, ADHD, and Alzheimer's disease, with some of these studies identifying novel risk genes. The specific findings of the glaucoma study are not clear in relation to these other conditions.