Tag: gene therapy

Severe Combined Immunodeficiency is a primary immune deficiency characterized by the severe defects in both the T- and B-lymphocyte systems. This usually results in the onset of one or more serious infections within the first few months of life. These infections are usually serious and may even be life-threatening, they may include pneumonia, meningitis or bloodstream infections. There are several forms of SCID. The most common type is linked to the X-chromosome, making this form affect only males. Other forms of SCID usually follow an autosomal recessive inheritance pattern or are the result of spontaneous mutations. One of these other forms is linked to a deficiency of the enzyme adenosine deaminase (ADA) while other cases of SCID are caused by a variety of other defects.

Retroviruses are a class of enveloped viruses that contain a single-stranded RNA genome. They are able to efficiently integrate permanently into the human genome after entering cells, where they provide the basis for permanent expression of foreign DNA. They offer several benefits like the integration of the gene of interest into chromosomes, stable expression, reducing a lot of unnecessary steps required when we go by gene therapy by other methods and the unique life cycle of the virus causing no immunogenicity.

Adenosine deaminase (ADA) deficiency can be treated by bone marrow transplantation, or by enzyme replacement therapy, in which functional ADA is given to the patient by injection. But permanent treatment can be done by introduction of gene isolated from bone marrow cells, which produces ADA, into the cells of the patient at early embryonic stage.

Gene therapy is a collection of methods that allows correction of gene defect that has been diagnosed in a child  for adenosine deaor embryo. An example of gene therapy is the introduction  of geneminase in persons suffering from ADA deficiency, a disorder caused due to the deletion of gene for adenosine deaminase. In some patients , it can be cured by bone marrow transplantation whereas in some by the enzyme replacement therapy

Gene therapy is a collection of methods, that allows correction of gene defect that has been diagnosed in a child/embryo. Correcting of a genetic defect involves delivery of a normal gene into the individual or embryo to take over the function of and compensate for the non-functional gene.

Gene therapy is a newly emerging branch of biotechnology with tremendous results. It is basically used for correcting genetic disorders. In gene therapy, normal genes are introduced in the cells to replace the missing genes or defective genes. 

Gene therapy is a collection of methods, that allows correction of a gene defect that has been diagnosed in a child embryo.

First successful gene transfer in human was performed by F.Anderson. Ashi Disilva a 4-year girl was treated by replacing ADA gene in lymphocytes.

Gene cloning is the process of making the copies of gene of interest by locating it in DNA followed by extraction of DNA containing that gene. A probe is a radiolabeled single-stranded DNA/ RNA fragment used to search for a gene of interest or other DNA sequence. For the purpose, the base sequence of probe is complementary to the target sequence to facilitate its base pairing with target gene. Gene multiplication is a mechanism that increase the genes in their number of copies. It is also called as gene amplification and is the source of evolution. Gene therapy is the process of introduction of DNA into living human beings in order to treat disease. It is used to replace a missing gene product or to correct mutant alleles. Correct answer is C.