abnormal chromatin silencing abnormal chromatin silencing at silent mating-type cassette abnormal chromatin silencing at silent mating-type cassette during mitotic cell cycle 2011-04-13T03:34:54Z FYPO:0000156 A transcription regulation phenotype observed in the vegetative growth phase of the life cycle in which chromatin silencing at the silent mating-type cassettes is abnormal. Chromatin silencing is the observed effect of processes that repress transcription in a region of the genome that is normally assembled into heterochromatin. midori Chromatin silencing phenotypes may reflect the assembly or maintenance of heterochromatin. See the GO cellular component term 'heterochromatin' (GO:0000792), and the biological process term 'heterochromatin organization' (GO:0070828). abnormal chromatin silencing at silent mating-type cassette during vegetative growth abnormal chromatin silencing at mating-type region heterochromatin