Gene therapy, Molecular Diagnosis,ELISA

1. Technique of Genetic Engineering to change a faulty gene by a healthy functional gene is called gene therapy, which was performed to a 4 year old girl with Adenosine deaminase (ADA) deficiency which will lead to severe combined Immuno deficiency (SCID).
2. Germline and somatic cell gene therapy are the two types of gene therapy out of which somatic cell therapy is only permitted.
3. The gene ADA was introduced into lymphocytes, which was extracted from the bone marrow and then re-injected to the patient’s bone marrow.
4. Periodic infusion of the genetically engineered lymphocytes was the only drawback of this technique.

Molecular diagnosis:

1. Early detection is possible only by rDNA Technology, PCR, ELISA (Enzyme Linked Immuno Sorbent Assay).
2. Specific DNA is identified from thousands of each by blotting technique.
3. Southern blotting – DNA identification, Northern blotting – RNA identification and Western blotting – Protein identification
4. Molecular probes [ss DNA with radioactive isotopes] are available for genetic disorders such a Tay-Sachs, Muscular dystrophy etc.,

ELISA

It is based on the Antigen-Antibody interaction and even can detect a very small amount of protein with the help of Horse-Radish Peroxidase (or) Alkaline Phosphatase enzyme, which produces coloured solution to detect the presence of disease causing gene in the sample.