Introduction Otters are mammals of the class amphibians that are mostly aquatic and feed on fish. Their bodies are generally slim with short limbs. They have characteristic long muscular tails. They are also known for their webbed toes that end in sharp claws adapted for their feeding habits. They are found almost in all parts of the world. This genetic review will focus on both the diversity of river otters and sea otters. River otters ( Lutra Canadensis) Lutra canadensis commonly found in North America like rivers with transparent waters with a high rate of flow and well-vegetated riverbanks. They enjoy living in mature trees deciduous trees alder, scrub and woodlands. In terms of habitat and diet, this species is opportunistic in nature and has to utilize a wide area of the river so as to meet the metabolic demands of the body. This species population has been known to be on the decline due to factors that include habitat destruction and unregulated fur harvest. Issues of pollution and trapping have also contributed to the loss of genetic diversity in this group of animals. Researchers have undertaken studies on river otters to determine diversity. For instance the introduction of 279 river otters in western New York between the long period of 1995 and 2000. Studies have been done on the faeces of the otters so as to determine dietary and genetic characteristics. For the reintroduced river otters genetic diversity can be determined using the technology of molecular scatology. The DNA material obtained from the faeces can be used for analysis to obtain the required information for genetic variability. The river otters are opportunistic feeders with their food mainly comprising of crayfish, frogs and aquatic insects. (Serfass, 26 1995) Breeding patterns in these species can be determined using the technology of scatology. The DNA materials were obtained from the faeces of those individuals who were reintroduced into the river. This DNA can then be subjected to laboratory tests. This method is good because it has no effect on the otters and to be particular their natural behaviour. In the group, the molecular technology can be used to determine where an individual otter came from therefore establish if there are instances of inbreeding. If inbreeding is noted in the analysis then measures can be put in place to prevent The phenomenon from occurring. Inbreeding can cause can give rise to weaker individuals in the population who cannot compete effectively with the rest. Therefore if instances of inbreeding are reduced in the breeding of the river otters then this will be a big step towards conserving the group and maintaining genetic diversity. The presence of raccoons in the population has also led to studies to determine if there exists a relationship between them and the river otters. Genetic similarities between the two species can be determined using molecular technology. (Amos, 87 2001) Suitable methodologies have been designed in such a way that possible visual cues can between the river otters and the raccoons can be determined. The genetic sample analysis can also be useful in determining if there exist differences between the river otter and the raccoon’s microsatellite s