What is DNA sequencing?

DNA sequencing is the process of determining the precise order of nucleotides within a DNA molecule. It includes any technology that is used to determine the order of the four bases viz., adenine, guanine, cytosine and thymine- in strand of DNA.  The DNA sequencing technology has been used in laboratories to uncover genes related to diseases.

DNA analysis is diagnostically proven as very useful and a sensitive tool. In this modern diagnostic DNA analyses can diagnose inherit genetic defect and also disease causing pathogen can be detected by identifying genes of that organism. The DNA analysis in disease diagnosis and medical forensics involves procedures like- hybridization technique, DNA profiling, etc. Few examples of DNA analysis in genetic disease diagnosis are:

• Sickle cell anemia can be detected by digesting mutant and normal β-globin gene and performing hybridization with a cloned β-globin DNA probe.
• Huntington’s disease can be diagnosed by the analysis of RFLPs in blood related individuals.
• Alzheimer’s disease, researchers have found a gene on chromosome number 21 which is believed to be responsible for inheriting this disease and they developed a DNA probe that located the genetic marker for this disease.

There are also diagnostic systems developed and are is underdevelopment to detect the disease by DNA analysis for diseases like- fragile X syndrome, Friedrich’s ataxia, cystic fibrosis, muscle dystrophy, diabetes, cancers, obesity, etc.