Campbell D, Doctor J S, Feuersanger J H, Doolittle M M
Genetics. 1981 Jun;98(2):239-55. doi: 10.1093/genetics/98.2.239.
The frequencies of recovered disomy among the meiotic segregants of yeast (Saccharomyces cerevisiae) triploids were assessed under conditions in which all 17 yeast chromosomes were monitored simultaneously. The studies employed inbred triploids, in which all homologous centromeres were identical by descent, and single haploid testers carrying genetic markers for all 17 linkage groups. The principal results include: (1) Ascospores from triploid meiosis germinate at frequencies comparable to those from normal diploids, but most fail to produce visible colonies due to the growth-retarding effects of high multiple disomy. (2) The probability of disome formation during triploid meiosis is the same for all chromosomes; disomy for any given chromosome does not exclude simultaneous disomy for any other chromosome. (3) The 17 yeast chromosomes fall into three frequency classes in terms of disome recovery. The results support the idea that multiply disomic meiotic segregants of the triploid experience repeated, nonrandom, post-germination mitotic chromosome losses (N + 1 leads to N) and that the observed variations in individual disome recovery are wholly attributable to inherent differences in disome mitotic stability.
在能同时监测酵母（酿酒酵母）三倍体减数分裂分离株中恢复的二体频率的条件下，对其进行了评估。这些研究使用了近交三倍体，其中所有同源着丝粒都因遗传而相同，以及携带所有17个连锁群遗传标记的单倍体测试菌株。主要结果包括：（1）三倍体减数分裂产生的子囊孢子萌发频率与正常二倍体产生的子囊孢子相当，但由于高度多重二体的生长抑制作用，大多数子囊孢子无法形成可见菌落。（2）三倍体减数分裂期间形成二体的概率对所有染色体来说都是相同的；任何给定染色体的二体并不排除其他任何染色体同时出现二体。（3）就二体恢复而言，17条酵母染色体可分为三个频率类别。这些结果支持这样一种观点，即三倍体的多重二体减数分裂分离株经历了反复的、非随机的、萌发后有丝分裂染色体丢失（N + 1导致N），并且观察到的个体二体恢复差异完全归因于二体有丝分裂稳定性的内在差异。
