Although 99.9% of human DNA sequence is the same in every person, enough of the DNA is different that it is possible to distinguish one individual from another, except monozygotic (MZ) or identical twins. MZ twins are formed when a single egg is fertilized to form one zygote which then divides into two separate embryos. As a result, identical twins have identical DNA sequences; thus, DNA fingerprint may be same in the case of monozygotic twins.