Silent domains are assembled continuously from the telomere and are defined by promoter distance and strength, and by SIR3 dosage.

In Saccharomyces cerevisiae, telomeres repress transcription of genes located nearby. This region-specific gene inactivation is thought to involve the packaging of telomeric domains into silent chromatin. To gain insight into the mechanism of telomeric silencing, a genetic assay to examine the spread of silencing along the distal right arm of chromosome V was developed.