Back in July 2015, a correlation between depression and two genetic loci was discovered. #CorrelationDoesNotImplyCausation
One is near SIRT1, the other is in an intron of LHPP.
2015 Jul 15 • Heidi Ledford • nature
Sparse whole-genome sequencing identifies two loci for major depressive disorder • 2015 Jul 30 • CONVERGE consortium • Nature
Sirtuins seem to be involved in RNA splicing, responsible for generating alternate transcripts.
The homologous gene in yeast is responsible for regulation of epigenetic silencing and suppressing rDNA recombination
SIRT1 is also associated with a form of xeroderma pigmentosum.
LHPP is not that well understood. It seems to be a mitochondrial enzyme associated with oxidative phosphorylation.