How do you differentiate between DNAs of two different organisms?

Answer 1

No two organisms have identical DNA, It depends on the molecular marker and species, DNA fingerprinting is a technique that is used to identify patterns that occur in DNA. One of the method consist using Restriction enzymes. Restriction enzymes always cut at the same base sequence. Because no two individuals have identical DNA, no two individuals will have the same length fragments. Different species of organisms have different proportions of bases.

Answer 2

DNA differences between two different organisms can be identified by comparing their DNA sequences. This can be done by sequencing the DNA of each organism and then aligning the sequences to look for differences such as single nucleotide polymorphisms (SNPs), insertions, deletions, or rearrangements. DNA fingerprinting techniques such as restriction fragment length polymorphism (RFLP) or polymerase chain reaction (PCR) can also be used to identify unique DNA patterns that distinguish between organisms.