The genetics of neuropsychiatric diseases: looking in and beyond the exome

Next-generation sequencing, which allows genome-wide detection of rare and de novo mutations, is transforming neuropsychiatric disease genetics through identifying on an unprecedented scale genes and protein-coding mutations that confer risk. Although understanding how regulatory variants influence risk remains a challenge, we are likely transitioning into a phase of neuropsychiatric disease genetics in which the rate-limiting step may no longer be gene discovery. Instead, the future will concentrate more on the biological and clinical translation of the torrent of specific risk mutations identified through next-generation sequencing. Here, we review the recent progress that resulted specifically from exome sequencing and emphasize the need for rigorous statistical evaluation of the expanding data sets, as well as expanded functional analysis of implicated proteins and mutations. Then, we introduce some of the expected opportunities and challenges investigators face when moving beyond the exome. Finally, we briefly highlight the challenge of deriving translational benefit from the progress in genetics.