Tag: genetics of the future

Questions Related to genetics of the future

Adenosine deaminase deficiency can be permanently cured by which of the following methods?

  1. Bone marrow transplantation

  2. Enzymes replacement therapy

  3. Gene therapy at early embryonic stages

  4. All of these


Correct Option: C
Explanation:

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.

..........is the transfer of normal genes into body cells to correct a genetic defect.

  1. gene therapy

  2. gene mutation

  3. nucleic acid hybridization

  4. reverse transcription


Correct Option: A
Explanation:

Gene therapy is a collection of methods that allow correction of a gene defect that has been diagnosed in a child/embryo. In this method, genes are inserted into a person's cells and tissues to treat a disease. Correction 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.

So, the correct option is 'gene therapy'.

Clot formation can be prevented by treatment with_______ in gene therapy.

  1. DNAase

  2. Recombinant vaccine

  3. TPA

  4. TGF-B


Correct Option: C

Gene therapy has been successful in curing genetic diseases in laboratory animals through

  1. Exposure to X-ray to rectify the defective gene

  2. Replacing the defective gene with a functional gene

  3. Oral delivery of genes

  4. Use of therapeutic medicines to rectify the defective genes


Correct Option: B

The first clinical gene therapy was done for the treatment of __________.

  1. AIDS

  2. Cancer

  3. Cystic fibrosis

  4. SCID (Serve Combined Immuno Deficiency resulting form deficiency of ADA)


Correct Option: D
Explanation:

The first clinical gene therapy was given in 1990 to a 4-years old girl with adenosine deaminase (ADA) deficiency. This enzymes is very important for the immune system to function. ADA deficiency can lead to severe combined immune deficiency (SCID). 

Diseases that are caused by the malfunction of a phototropic gene are:

  1. Cured by dietary restrictions

  2. Reversible by gene therapy

  3. Called as syndromes

  4. Extremely rare


Correct Option: B
Explanation:
Phototropism is the growth of an organism which responds to a light stimulus. It is most often observed in plants, but can also occur in other organisms such as fungi. The cells on the plant that are farthest from the light have a chemical called auxin that reacts when phototropism occurs. Gene therapy is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient's cells instead of using drugs or surgery. 
So the correct option is 'Reversible by gene therapy'.

Which of the following statements regarding gene therapy is/are correct? 

  1. It is an application of biotechnology, in which a defective gene is manipulated by introduction of a normal, healthy and functional gene.

  2. The genetic disorders that are being investigated for gene therapy, range from sickle-cell anemia to server combined immuno-deficiency (SCDI).

  3. The first clinical gene therapy was given in 1990 to a 4-year old girl with adenosine deaminase (ADA) deficiency.

  4. All of the above


Correct Option: D
Explanation:
Gene therapy is a technique for correcting defective genes responsible for disease development. Under intensive investigation are, disease ranging from the rare genetic diseases caused by single mutations like sickle cell anaemia to killer diseases such as server combined immuno-deficiency (SCID). The first clinical gene therapy was given in 1990 to a 4-years old girl with adenosine deaminase (ADA) deficiency. This enzymes is very important for the immune system to function. ADA deficiency can lead to severe combined immuno-deficiency (SCID).
So, the correct answer is 'All of the above'.

Assertion : SCID is a primary immunodeficiency.

Reason : It is a serious congenital immunodeficiency.

  1. Both the Assertion and the Reason are true and the Reason is a correct explanation of the Assertion.

  2. Both the Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.

  3. The Assertion is true but the Reason is false.

  4. Both the Assertion and Reason are false.

  5. The Assertion is false but Reason is true.


Correct Option: A
Explanation:

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.

What is the benefit of using a retrovirus as a vector in gene therapy?

  1. It is not able to enter cells

  2. It eliminates a lot of unnecessary steps

  3. It incorporates the foreign gene into the host chromosome

  4. Both (b) and (C)


Correct Option: D
Explanation:

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.

So, the correct option is 'Both (b) and (C)'.

What is the permanent cure of adenosine deaminase (ADA) deficiency in children?

  1. Bone marrow transplantation

  2. Enzyme replacement therapy in which functional ADA is given to patient by injection

  3. Infusion of genetically engineered lymphocytes (in which functional ADA-cDNA is introduced) into the patient's blood

  4. Introduction of gene isolated from the bone marrow cells which produce ADA, into the cells of the patient at early embryonic stages


Correct Option: D
Explanation:

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.