Almost about 440 million STR markers exist in the genome of creatures that most of them have polymorphic alleles with different lengths. The difference in the length of alleles is due to the difference in the number of times that the main monomer sequence has been repeated. These polymorphisms include Single Nucleotide Polymorphism (SNP), Restriction Fragment Length Polymorphism (RELP), and minisatellite and microsatellite sequences. There are many DNA polymorphism uses in different settings such as gene mapping and fingerprinting and identity tests.