A cell phenotype in which minichromosomes are lost at a higher frequency than normal. Minichromosome loss occurs when one or both daughter cells do not inherit copies of a minichromosome from the mother cell, and may result from failure of minichromosome replication or segregation. [ https://www.pombase.org/gene/mah ]
Term information
Note that in budding yeast, increased plasmid loss is often called a minichromosome maintenance defect, because "minichromosome" is roughly synonymous with an autonomously replicated and segregated plasmid in that organism. In fission yeast, a minichromosome is a large portion of a chromosome, usually about half of chromosome 3, that replicates and segregates autonomously. For smaller autonomously replicating and segregating constructs, consider 'increased plasmid loss' (FYPO:0000786).