Among the neurons in the human brain, somatically derived copy number variations are frequent. Copy number variations show wide variability (9 to 100% of brain neurons in different studies). Most alterations are between 2 and 10 Mb in size with deletions far outnumbering amplifications. Copy number variations appear to be higher in brain cells than in other cell types. A likely source of copy number variation is incorrect repair of DNA damage.
Genomic duplication and triplication of the gene appear to be a rare cause of Parkinson's disease, although more common than point mutations.
Copy number variants in RCL1 gene are associated with a range of neuropsychiatric phenotypes in children.