Genome sequencing in nematodes and its application

Every organism, may be an animal or a plant, has different gene within them. Genes are the locatable regions of genomic sequences, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed regions, and or other functional sequence regions (Pearson, 2006 and Pennisi, 2007). The sum total of the entire gene in an organism is known as Genome. It is encoded either in DNA or, for many types of viruses in RNA. The process of determining the precise order of nucleotides within a DNA molecule is called as genome sequencing. The first DNA sequencing method was Maxam-Gilbert sequencing method (Maxam and Gilbert, 1977) and later on many methods have been developed by many scientists for genome sequencing. Among them, Shotgun sequencing (Staden, 1979) is one of the important and widely used methods in the field of Nematology. Caenorhabditis elegans is the first multicellular organism whose genome is completely sequenced having 97Mb (now 100Mb) (The C. elegans Sequencing Consortium, 1998). With the help of genome sequencing, detection of particular nematode and study on genetic variations can be done with accurate result and, it also helps in generating a new PCR primer specific for a nematode. The functional gene identified in genome sequencing helps to know the mechanism of parasitism in the host which will play an important role in nematode disease management; ultimately it will give a boon in the science of agriculture.