Molecular Probes: Segments of DNA or RNA with the help of which cDNA or RNA segments of any organism present in it can be identified are called molecular probes. The molecular probes are of two types. DNA probes. RNA probes. Importance of Probes: These are used to identify specific DNA segments used in the research of genetic engineering. Pollutants in food can be detected with the help of probes. These are used in the field of forensic science, in resolving disputed paternity issues and establishing the family relationship. These can be used to identify an improved variety of crops and hybridized seeds of crops.