   siRNAs are incorporated into RNA-                    The first clinical gene therapy was given
    induced silencing complex (RISC)                      in 1990 to a 4-yr old girl with adenosine
   Guided by base complementarity of the                 deaminase (ADA) deficiency.
    siRNA, the RISC targets mRNA for                     This enzyme is required for breakdown of
    degradation.                                          deoxyadenosine into uric acids.
   The consequence was that the parasite                In the absence of ADA toxic
    could not survive in a transgenic host.               deoxyadenosine is accumulated and
                                                          destroy the infection fighting immune
Biotechnological Applications in Medicine                 cells called T-cells and B-cells.
                                                         This disorder is caused due to the deletion
   Biotechnology enables mass production of              of the gene for adenosine deaminase in
    safe and more effective therapeutic drugs.            chromosome 20.
   Recombinant therapeutics does not induce
    unwanted immunological responses as is            Test tube baby
    common in case of similar products
    isolated from non-human sources.                     A test tube baby is the term that refers to a
                                                          child that is conceived outside the
Genetically Engineered Insulin                            woman"s body. The process is referred to
                                                          as "in vitro" (outside the body)
   Taking insulin at regular interval of time is         fertilization.
    required for adult-onset diabetes.                   The World’s first test tube baby (girl)
   Previously the source of insulin was the              named as Louise Joy Brown was born on
    slaughtered cattle and pigs.                          July 25, 1978 in Great Britain.
   This insulin caused allergy in some                  India’s first test tube baby (girl) as named
    patients.                                             as Harsha was born in Mumbai on August
   Each insulin made of two short                        6, 1986.
    polypeptide chains; chain A and chain B
    that are linked together by disulphide            Cloning
   Insulin synthesized in pancreas as pro-           Cloning describes the processes used to create
    hormone which is a single polypeptide             an exact genetic replica of another cell, tissue
    with an extra stretch called C-peptide.           or organism. The copied material, which has
   C-peptide is removed during matured               the same genetic makeup as the original, is
    insulin.                                          referred to as a clone.
   In 1983 Eli Lilly an American company
                                                      Dolly, a Sheep, was the first mammal to have
    prepared       two       DNA      sequences
                                                      been successfully cloned from an adult cell by
    corresponding to A and B, chains of
                                                      Dr. Ian Wilmut, UK.
    human insulin and introduced them in
    plasmids of E.coli to produce insulin             Noori is a female pashmina goat, the first
    chains.                                           pashmina goat to be cloned using the process
   Chain A and chain B produced separately,          of nuclear transfer.
    extracted and combined by creating
    disulfide bonds to form mature human              There are three different types of cloning:
                                                      Gene cloning, which creates copies of genes
Gene therapy                                          or segments of DNA
   Gene therapy is an attempt to cure                Reproductive cloning, which creates copies
    hereditary or genetic diseases.                   of whole animals
   Genes are inserted into a person’s cells
    and tissue to treat the disease.                  Therapeutic        cloning,     which      creates
                                                      embryonic stem cells. Researchers hope to use
                                                      these cells to grow healthy tissue to replace
                                                      injured or diseased tissues in the human body.