Nullisomy is an aneuploid condition in which a pair of homologous chromosomes is deficient and represented as 2n−2 Monosomy is an aneuploid condition in which a chromosome is deficient from its homologue and represented as 2n−1 . Trisomy is an aneuploid which has one extra chromosome and represented as 2n+1 . Polyploidy is the phenomenon of having more than two genomes or set of chromosomes i.e., 3n− triploidy 4n− tetraploidy 5n− pentaploidy.