Medical Definition of nullisomic
(Entry 1 of 2) : having two less than the diploid number of chromosomes due to loss of one chromosome pair. nullisomic. noun.
What is Nullisomic in biology?
Nullisomy is a genome mutation where a pair of homologous chromosomes that would normally be present is missing. Thus, in nullisomy, two chromosomes are missing, and the chromosomal composition is represented by 2N-2.
What is trisomy in biology?
(TRY-soh-mee) The presence of an extra chromosome in some or all of the body's cells. This results in a total of three copies of that chromosome instead of the normal two copies. For example, Down syndrome (trisomy 21) is caused by having three copies of chromosome 21 instead of the usual two copies.
