Biotechnological Applications in Medicine Questions in English

(D) Human insulin is produced using recombinant $DNA$ technology. The gene for human insulin is inserted into the bacterium $Escherichia$ $coli$ $(E. coli)$ to produce the insulin protein. This process allows for the large-scale production of insulin that is identical to the natural human hormone.

(D) The $ADA$ (Adenosine Deaminase) deficiency is caused by the deletion of the gene for adenosine deaminase.
While enzyme replacement therapy and periodic infusion of lymphocytes are treatments,they are not permanent cures as they require repeated administration.
The only permanent cure for $ADA$ deficiency is to introduce cells producing $ADA$ into the patient at an early embryonic stage.
If the gene isolated from marrow cells producing $ADA$ is introduced into cells at early embryonic stages,it can be a permanent cure.

(B) The first clinical gene therapy was performed in $1990$ on a $4$-year-old girl with adenosine deaminase $(ADA)$ deficiency.
$ADA$ deficiency is caused by the deletion of the gene for adenosine deaminase,which is crucial for the proper functioning of the immune system.
In this therapy,lymphocytes from the patient's blood were grown in a culture outside the body,and a functional $ADA$ $cDNA$ was introduced into these lymphocytes using a retroviral vector.
These genetically engineered lymphocytes were then returned to the patient's body.

(D) $E. coli$ (Escherichia coli) is a widely used bacterium in biotechnology for the production of recombinant proteins.
Among the given options,$E. coli$ is used for the production of human Interferon (specifically alpha-interferon) through recombinant $DNA$ technology.
Rifampicin is an antibiotic produced by bacteria like Amycolatopsis rifamycinica.
$LH$ (Luteinizing Hormone) is a glycoprotein hormone produced by the pituitary gland.
Ecdysone is a steroid prohormone of the insect molting hormone $20-$hydroxyecdysone.

(B) The use of living organisms or their components to produce products and processes that are useful to humans is known as $Applied \ Biology$ or more specifically,$Biotechnology$. Among the given options,$Applied \ Biology$ is the most appropriate term that encompasses the application of biological knowledge for human welfare.

(C) The chemical structure of human insulin was determined by Frederick Sanger in $1953$. He was awarded the Nobel Prize in Chemistry in $1958$ for his work on the structure of proteins,especially that of insulin. Insulin is a peptide hormone consisting of two polypeptide chains,chain $A$ and chain $B$,linked by disulfide bridges.

(C) Biotechnology,specifically recombinant $DNA$ technology,is used to produce human insulin on an industrial scale. Previously,insulin was extracted from the pancreas of slaughtered cattle and pigs,which often caused allergic reactions in some patients. By inserting the human insulin gene into $E. coli$ bacteria,scientists can produce large quantities of pure human insulin,which is safer and more effective for treating diabetes mellitus.

(B) Recombinant $DNA$ technology allows for the production of antigenic polypeptides of pathogens in bacteria or yeast.
$Hepatitis-B$ vaccine is the first commercially available human vaccine produced using recombinant $DNA$ technology.
It is produced by inserting the gene for the $Hepatitis-B$ surface antigen $(HBsAg)$ into yeast cells,which then produce the antigen for use in the vaccine.

(A) The Hepatitis $B$ vaccine is a recombinant $DNA$ vaccine. It is produced by inserting the gene encoding the Hepatitis $B$ surface antigen $(HBsAg)$ into yeast cells $(Saccharomyces \, cerevisiae)$. The yeast cells then express the antigen, which is harvested and purified to create the vaccine.

(A) Recombinant $DNA$ technology allows for the production of safer and more effective vaccines,often referred to as second-generation vaccines.
In this process,the gene encoding the antigenic protein of a pathogen is isolated and inserted into a suitable host organism.
$Yeast$ (e.g.,$Saccharomyces$ $cerevisiae$) and $Bacteria$ (e.g.,$Escherichia$ $coli$) are the most commonly used host organisms for this purpose because they are easy to culture,grow rapidly,and can express foreign genes efficiently to produce the desired antigens.

(D) Recombinant $DNA$ technology allows for the production of vaccines by inserting specific genes into host organisms.
Both yeast (e.g.,$Saccharomyces$ $cerevisiae$) and bacteria (e.g.,$Escherichia$ $coli$) are commonly used as host systems for the expression of recombinant proteins,including antigens used in vaccines.
For example,the Hepatitis $B$ vaccine is produced using recombinant yeast cells.
Therefore,both yeast and bacteria are utilized in this technology.

(A) The Hepatitis-$B$ vaccine is a recombinant vaccine produced using yeast cells.
In this process,the gene encoding the Hepatitis-$B$ surface antigen $(HBsAg)$ is inserted into the yeast genome.
The yeast cells then express this antigen,which is harvested,purified,and used as a vaccine to provide immunity against the Hepatitis-$B$ virus.

(D) The vaccine for Hepatitis-$B$ is a recombinant $DNA$ vaccine.
It is produced using yeast cells $(Saccharomyces \, cerevisiae)$ as a host.
The gene encoding the Hepatitis-$B$ surface antigen $(HBsAg)$ is inserted into the yeast genome.
The yeast cells then express this antigen, which is harvested, purified, and used as a vaccine to induce an immune response in humans.

(B) $CT$ scan (Computed Tomography scan) uses $X$-rays to create detailed cross-sectional images of the body.
It rotates an $X$-ray source and detectors around the patient to capture multiple images from different angles,which are then processed by a computer to generate a $3D$ view of internal structures.

(A) $MRI$ stands for Magnetic Resonance Imaging.
It uses strong magnetic fields and non-ionizing electromagnetic waves to accurately detect pathological and physiological changes in the living tissue of the body.
Unlike $X$-rays or $\gamma$-rays,which are ionizing radiations and can cause $DNA$ damage,$MRI$ is considered safer because it does not use ionizing radiation.
Therefore,only $(ii)$ is the correct component used in $MRI$ for this purpose. Since the provided options are incomplete or potentially misleading based on standard curriculum,the most accurate choice focusing on the primary mechanism is $(ii)$.

(D) Microbes are used for human welfare through the application of $Biotechnology$ and $Genetic Engineering$. $Biotechnology$ involves the use of living organisms or their products to improve human health and food systems. $Genetic Engineering$ is a branch of $Biotechnology$ that involves the manipulation of genetic material to produce desired traits or products. Therefore,both fields contribute significantly to the industrial and medical applications of microbes.

(B) Proteins are complex macromolecules that maintain their structure through various interactions like hydrogen bonds,disulfide bridges,and hydrophobic interactions.
High-energy ionizing radiations,such as $ \gamma $-rays,possess sufficient energy to break these chemical bonds and disrupt the tertiary and secondary structures of proteins.
This process,known as denaturation,leads to the loss of biological activity and the destruction of the protein molecule.
Therefore,$ \gamma $-rays are highly effective in causing the destruction of proteins.

(B) The correct answer is $(B)$.
$ADA$ deficiency is caused by the deletion of the gene for adenosine deaminase.
While enzyme replacement therapy and periodic infusion of genetically engineered lymphocytes are treatments,they are not permanent cures as they require repeated administration.
$A$ permanent cure can be achieved by gene therapy,specifically by introducing the functional $ADA$ gene isolated from bone marrow cells into cells at early embryonic stages,which allows the gene to be present in all cells of the developing organism.

(A) : Gene therapy is a technique of genetic engineering which involves the replacement of a faulty or disease-causing gene with a normal,healthy,functional gene.
In $1990$,the first clinical gene therapy was administered to a $4$-year-old girl suffering from adenosine deaminase $(ADA)$ deficiency.
This enzyme is crucial for the proper functioning of the immune system.
$A$ deficiency of this enzyme leads to severe combined immunodeficiency $(SCID)$.

(B) Human insulin is composed of $51$ amino acids arranged in two polypeptide chains.
Chain $A$ consists of $21$ amino acids,and chain $B$ consists of $30$ amino acids.
These two polypeptide chains are interconnected by disulphide bridges (or $S-S$ linkages).

(A) : Recombinant $DNA$ technology has significantly impacted healthcare by enabling the mass production of safe and effective therapeutic drugs.
In $1983$, the American company Eli Lily first synthesized two $DNA$ sequences corresponding to the $A$ and $B$ chains of human insulin.
These sequences were introduced into plasmids of $Escherichia \text{ } coli$ to produce the insulin chains.
The $A$ and $B$ chains were produced separately, extracted, and then combined by creating disulfide bonds to form functional human insulin, known as humulin.

(A) : Gene therapy is a corrective therapy used to treat diseases caused by genetic defects.
In this process,functional genes are inserted into a patient's cells or tissues to replace or compensate for the defective gene.
Viral vectors,such as $Adenovirus$ or $Retrovirus$,are commonly used to deliver the normal,functional gene into the target cells because of their high efficiency in infecting human cells.

(D) The correct answer is $(d)$.
Gene therapy is a collection of methods that allows the correction of a gene defect that has been diagnosed in a child or embryo.
In this process,functional genes are inserted into a person's cells and tissues to treat a disease.
Correction of a genetic defect involves the delivery of a normal gene into the individual or embryo to take over the function of and compensate for the non-functional gene.
The first clinical gene therapy was given in $1990$ to a $4$-year-old girl suffering from adenosine deaminase $(ADA)$ deficiency.
This enzyme is crucial for the proper functioning of the immune system.
$SCID$ (Severe Combined Immunodeficiency) is caused due to a defect in the gene responsible for the enzyme adenosine deaminase.
In some children,$ADA$ deficiency can be cured by bone marrow transplantation or by introducing the functional gene into cells at early embryonic stages,which can provide a permanent cure.

(D) : Insulin is now being commercially produced by genetic engineering. Insulin consists of two short polypeptide chains: chain $A$ and chain $B$,that are linked together by disulphide bonds.
Insulin,in mammals,is synthesized as a prohormone which contains an extra stretch called the $C$-peptide. During maturation,this $C$-peptide is removed.
The production of insulin could only have been commercially possible if the maturation process of $C$-peptide was bypassed.
This problem was solved in $1983$ by Eli Lilly,an American company,which prepared functional insulin from two $DNA$ sequences corresponding to $A$ and $B$ chains of human insulin and introduced them into plasmids of $E. coli$ to produce insulin chains.
In this way,chains $A$ and $B$ were produced separately,extracted,and combined by creating disulfide bonds to obtain human insulin.

(C) The correct answer is $(C)$.
Insulin is now being commercially produced by genetic engineering.
Human insulin consists of two short polypeptide chains, chain $A$ and chain $B$, which are linked together by disulphide bonds.
In mammals, insulin is synthesized as a prohormone containing an extra stretch called the $C$-peptide, which is removed during maturation.
In $1983$, Eli Lilly, an American company, prepared functional insulin by introducing two $DNA$ sequences corresponding to the $A$ and $B$ chains of human insulin into the plasmids of $Escherichia$ $coli$ $(E. coli)$.
These chains were produced separately, extracted, and then combined by creating disulphide bonds to form mature human insulin.

(C) The Hepatitis $B$ vaccine is a recombinant $DNA$ vaccine.
It is produced by inserting the gene that codes for the Hepatitis $B$ surface antigen $(HBsAg)$ into the genome of the yeast $Saccharomyces$ $cerevisiae$.
The yeast cells then express the antigen, which is purified and used as the vaccine.
Therefore, the correct answer is $C$ (Yeast).

(B) $ADA$ deficiency is caused by the deletion of the gene for adenosine deaminase.
In some children,it can be cured by bone marrow transplantation,where the defective cells are replaced by healthy ones.
Another method is enzyme replacement therapy,in which functional $ADA$ is injected into the patient.
Gene therapy is also a potential cure,where functional genes are introduced into the patient's cells.

(B) $ELISA$ stands for Enzyme-Linked Immunosorbent Assay.
It is a diagnostic technique used to detect the presence of specific antigens or antibodies in a sample.
The fundamental principle of $ELISA$ is the specific interaction between an antigen and its corresponding antibody.
In this process,an enzyme-linked antibody is used to detect the binding,which produces a color change indicating a positive result.

(D) In humans,insulin is synthesized as a pro-hormone containing an extra stretch called the $C$-peptide.
This $C$-peptide is not present in the mature insulin and is removed during maturation.
The main challenge for the production of insulin using $r-DNA$ technology was getting insulin assembled into a mature form.
Eli Lilly,an American company,prepared two $DNA$ sequences corresponding to $A$ and $B$ chains of human insulin and introduced them in plasmids of $E. coli$ to produce insulin chains.
These chains were then extracted and combined by creating disulfide bonds to form mature human insulin.

(A) In the treatment of $ADA$ (Adenosine Deaminase) deficiency,gene therapy is used.
In this process,lymphocytes from the patient's blood are grown in a culture outside the body.
$A$ functional $ADA$ $cDNA$ is introduced into these lymphocytes using a retroviral vector.
The genetically engineered lymphocytes are then returned to the patient's body.
Retroviral vectors are preferred because they can integrate the foreign gene into the host genome,ensuring stable expression.

(C) Genetically engineered bacteria, specifically $Escherichia coli$, are widely used in the commercial production of human insulin (also known as Humulin).
This process involves inserting the human insulin gene into the bacterial plasmid, which then directs the bacteria to synthesize the insulin protein.
This method replaced the older practice of extracting insulin from the pancreases of slaughtered cattle and pigs, which often caused allergic reactions in patients.

(B) Proinsulin is a precursor molecule that consists of three chains: $A$,$B$,and $C$.
During the maturation process,the $C$-peptide,which is an extra stretch of amino acids,is removed from the proinsulin molecule.
This removal results in the formation of mature insulin,which consists of the $A$ and $B$ chains linked together by disulphide bridges.
Therefore,the maturation of proinsulin into insulin occurs after the removal of the $C$-peptide.

(D) The first clinical gene therapy was given in $1990$ to a $4$-year-old girl with Adenosine Deaminase $(ADA)$ deficiency.
$ADA$ enzyme is crucial for the immune system to function.
This deficiency leads to Severe Combined Immunodeficiency $(SCID)$.
In this therapy,lymphocytes from the patient's blood were grown in a culture outside the body,and a functional $ADA$ $cDNA$ was introduced into these lymphocytes using a retroviral vector,which were then returned to the patient.

(A) Gene therapy is a technique used to correct a defective gene by introducing a functional gene,matching with $(1)$.
$(B)$ Humulin is the first genetically engineered insulin used for the treatment of diabetes,matching with $(4)$.
$(C)$ $A$ probe is a single-stranded $DNA$ or $RNA$ molecule tagged with a radioactive molecule used to detect complementary sequences,matching with $(2)$.
$(D)$ $ELISA$ (Enzyme-Linked Immunosorbent Assay) is a diagnostic test based on antigen-antibody interactions,matching with $(3)$.
Therefore,the correct matching is $A-1, B-4, C-2, D-3$.

(A) $Bio-patent$ is a patent granted by a government to an inventor for biological inventions.
It grants the inventor the exclusive right to use,manufacture,or sell a biological invention for a specific period.
These inventions can include genetically modified organisms,biological processes,or products derived from biological resources.
Therefore,it is essentially the right to use an invention related to biological entities.

(D) Statement $I$ is correct: Human insulin consists of $51$ amino acids arranged in two polypeptide chains (chain $A$ with $21$ amino acids and chain $B$ with $30$ amino acids).
Statement $II$ is correct: The two polypeptide chains are linked together by two disulphide bridges.
Statement $III$ is correct: Insulin is synthesised as a pro-hormone (pro-insulin),which contains an extra stretch of amino acids known as the $C$-peptide.
Statement $IV$ is correct: During the maturation process,the $C$-peptide is removed from the pro-insulin to form mature,functional insulin. Therefore,$C$-peptide is not present in mature insulin.
Since all statements are correct,the correct option is $D$.

(A) The diagram illustrates the maturation of pro-insulin into functional insulin.
Pro-insulin consists of three polypeptide chains: $A$,$B$,and $C$.
The $C$-peptide is a stretch of amino acids that connects the $A$ and $B$ chains.
During the maturation process,the $C$-peptide is removed,leaving behind the $A$ and $B$ chains,which are then linked together by disulfide bonds to form mature,active insulin.

(B) Hybridoma cells are created by the fusion of a specific antibody-producing $B$-cell (lymphocyte) and a myeloma cell (a type of cancer cell).
These hybrid cells combine the ability to produce a specific antibody (from the $B$-cell) with the ability to divide indefinitely in culture (from the myeloma cell).
Therefore,hybridoma cells are hybrid cells produced from myeloma cells.

(C) $ELISA$ (Enzyme-Linked Immunosorbent Assay) is a diagnostic technique used to detect the presence of antigens or antibodies in a sample.
In the context of viral detection,$ELISA$ utilizes an enzyme-linked antibody to identify viral antigens.
The enzyme commonly used as a reporter molecule in this process is alkaline phosphatase or horseradish peroxidase.
These enzymes catalyze a reaction that produces a detectable color change,confirming the presence of the virus.

(A) $ELISA$ (Enzyme-Linked Immunosorbent Assay) is a diagnostic technique based on the principle of antigen-antibody interaction.
In this technique,an enzyme is linked to an antibody or antigen to detect the presence of a specific pathogen (like a virus).
The most commonly used enzyme as a key reagent in $ELISA$ is alkaline phosphatase or horseradish peroxidase,which produces a color change upon reacting with its substrate,indicating the presence of the virus.

(C) Adenosine Deaminase $(ADA)$ deficiency is caused by the deletion of the gene for $ADA$.
$1$. Enzyme replacement therapy and periodic infusion of genetically engineered lymphocytes are temporary solutions because these cells are not immortal and require repeated treatment.
$2$. Gene therapy is the permanent cure.
$3$. If the gene isolate from marrow cells producing $ADA$ is introduced into cells at early embryonic stages,it provides a permanent cure because these cells become part of the individual's genome and continue to produce the functional enzyme throughout the person's life.

(A) The commercial production of human insulin is achieved using recombinant $DNA$ technology. The gene for human insulin is inserted into the bacterium $Escherichia \ coli$ $(E. \ coli)$. This bacterium acts as a host to express the insulin protein,which is then extracted and purified for medical use. Therefore,$Escherichia \ coli$ is the correct organism used for this purpose.

(A) The first human hormone produced using recombinant $DNA$ technology is $Insulin$.
In $1983$,the American company $Eli$ $Lilly$ prepared two $DNA$ sequences corresponding to $A$ and $B$ chains of human $Insulin$ and introduced them in plasmids of $E. coli$ to produce insulin chains.
These chains were extracted and combined by creating disulfide bonds to form human $Insulin$ (Humulin).

(C) The first clinical gene therapy was given in $1990$ to a four-year-old girl with adenosine deaminase $(ADA)$ deficiency.
In this procedure,lymphocytes from the patient's blood were grown in a culture outside the body.
$A$ functional $ADA$ cDNA (using a retroviral vector) was then introduced into these lymphocytes,which were subsequently returned to the patient.
Since these cells are not immortal,the patient requires periodic infusion of such genetically engineered lymphocytes.

(C) Human insulin is synthesized as a pro-hormone containing an extra stretch called the $C$-peptide.
This $C$-peptide is removed during maturation to form mature insulin.
Mature insulin consists of two short polypeptide chains,chain $A$ and chain $B$,that are linked together by disulfide bridges (disulfide bonds).

(D) Retroviruses have the natural ability to infect host cells and integrate their genetic material into the host genome.
In biotechnology,disarmed retroviruses are used as vectors to deliver desired genes into animal cells,including human lymphocytes.
$pBR\,322$ is a plasmid vector used in bacteria.
$Ti\,plasmid$ is used for gene transfer in plants.
$\lambda$ phage is a bacteriophage used as a cloning vector in bacteria.
Therefore,the correct option is $D$.

(B) $ELISA$ (Enzyme-Linked Immunosorbent Assay) is a fundamental tool of clinical immunology.
It is based on the principle of antigen-antibody interaction,where specific antibodies or antigens are used to detect the presence of the target molecule.
This test is widely used as an initial screen for $HIV$ detection and allows for easy visualization of results through enzymatic color changes.

(A) Gene therapy is an experimental technique that uses genes to treat or prevent disease.
The first clinical gene therapy was performed in $1990$ to treat adenosine deaminase deficiency.
$A$ four-year-old girl became the first patient to receive gene therapy on September $14, 1990$,at the $NIH$ Clinical Center.
Adenosine deaminase deficiency,also known as $ADA$ deficiency or $ADA-SCID$,is an autosomal recessive metabolic disorder that leads to severe combined immunodeficiency.
This condition is caused by the lack of the enzyme adenosine deaminase,which is essential for the proper functioning of the immune system.

(A) $(i)$ Human insulin - Used for the treatment of Diabetes.
$(ii)$ Human growth hormone - Used for the treatment of Dwarfism.
$(iii)$ Blood clotting factor $VIII$ - Used for the treatment of Hemophilia.
$(iv)$ $TPA$ (Tissue Plasminogen Activator) - Used for the treatment of heart attacks and strokes.
$(v)$ $PDGF$ (Platelet-Derived Growth Factor) - Used to stimulate wound healing.
$(vi)$ Interferon - Used for the treatment of viral infections and certain cancers.
$(vii)$ Interleukin - Used to enhance immune reactions.
$(viii)$ Hepatitis $B$ vaccine - Used for the prevention of infection caused by the Hepatitis $B$ virus.
$(ix)$ Erythropoietin - Used to treat anemia associated with chronic kidney disease.
$(x)$ $DNase$ $I$ - Used for the treatment of cystic fibrosis.