Zygosity

Diploid organisms carry two alleles: one inherited from the the male parent and the second from the female parent. Zygosity indicates the similarity of the two alleles for one particular trait, i.e. whether they have the same or different DNA sequence.

Four different genotypes at a single locus are found in diploid organisms:

• Heterozygous
• Homozygous
• Hemizygous
• Nullizygous