Nullisomy

a type of genome mutation in which a pair of chromosomes that are normally present in the genome is missing. Organisms that exhibit nullisomy are called nullisomes. Nullisomy, especially in higher animals, usually results in death. Viable nullisomes can be found among polyploid plants; these nullisomes are used for nullisomic analysis and for establishing new, commercially valuable strains. Nullisomic analysis is used to determine genetic linkage groups and to study the traits that are controlled by these groups. The method is also applied to tissue-culture studies of human nullisomic cells.