What is the impact of rare variants?

The impact of rare variants is significant when studying diseases such as Alzheimer's. According to Manolis Kellis, rare variants, along with common and somatic variants, contribute to genetic diversity in the brain. This diversity is crucial as it affects different brain regions and functions differently, which can significantly impact disease progression and mental functions.

Rare variants, when combined with common and somatic variants, create a complex genetic mosaic that influences how diseases like Alzheimer's progress and affect cognitive functions. Manolis Kellis emphasizes their unique effects on neuronal functions and other brain-specific processes, differing substantially from common variants. The study of these variants at the cellular level, enabled by advanced technologies like single-cell RNA sequencing, helps in understanding how these genetic variations correspond to changes in gene expression and disease manifestation 1.