Molecular diagnosis.

Molecular diagnosis  

It is well known that an early diagnosis is very important for effective treatment of the disease

Methods of Molecular Diagnosis

1) Tradition method include conventional report in which early detection is not possible. This involve serum and urine analysis.

2) Molecular method include modern methods in which early detection is possible. They involve recombinant DNA technology (RDT), polymerase chain reaction etc. 

Some of the popular test to diagnose a particular disease 

 Polymerase chain reaction -: This method was developed in 1985 by Kary Mullis   

                                       

Principle :- 

PCR is a process of amplification of the nucleic acid. In         this method nucleic acid(DNA) of bacteria is taken amplification. It is important to note that the low concentration of bacteria or virus can be easily detected by amplification of their nucleic acid.

Applications :-

PCR is now routinely used to detect HIV in suspected AIDS patient .

It is being used to detect mutation in genes of suspected cancer patients. PCR is used to detect genetic diseases in foetuses before their birth. 

Medicine for SCID ???

 What is SCID ?

Severe combined immunodeficiency (SCID) is an uncommon hereditary problem described by the upset advancement of useful T cells and B cells brought about by various hereditary changes that bring about varying clinical presentations.

SCID includes faulty neutraliser reaction because of either direct inclusion with B lymphocytes or through inappropriate B lymphocyte initiation because of non-useful T-partner cells.

both"arms" (B cells and T cells) of the versatile safe framework are weakened because of a deformity in one of a few potential qualities.

 SCID is the most serious type of essential immunodeficiencies and there are currently at any rate nine diverse known qualities in which transformations lead to a type of SCID.

 It is otherwise called the air pocket kid illness and air pocket child sickness since its casualties are amazingly powerless against irresistible infections and some of them, for example, David Vetter, have gotten renowned for living in a sterile climate. SCID is the consequence of a safe framework so profoundly undermined that it is considered practically missing.

So would be thinking what bio-technology has provide in return.

So for your kind information bio-tech has provided a solution that is "Gene Therapy"

I Know, I know that my audience is inquisitive in knowing everything, there are many question in your mind. We"ll go step by step:- 

 What is Gene therapy ?

Gene therapy is a collection of method that allows correction of a gene defect  that has been diagnosed in the child or embryo. Here genes are inserted into person's cell and tissue to treat the 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 nonfunctional gene. 

Has Gene therapy been practiced ?

First Gene Therapy, The first landmark gene therapy was performed at National institute of Health (NIH),USA by W. French Anderson and Michael Blaese. 

In September 1990 they treated a 4 year old girl for inherited immunodeficiency called Severe combined immunodeficiency (SCID) also referred to as adenosine deaminase deficiency (ADA)

Method of Gene Therapy for SCID Disease ?

SCID is caused by a defect in the gene for the enzyme adenosine deaminase. The patient have SCID do not have functioning T-Lymphocytes and therefore, they cannot provide immune responses against invading pathogen.

The ideal approach is to give a patient a functioning ADA that breaks down toxic biological product.

1) A normal human gene, encoding the enzyme adenosine deaminase is introduced into retrovirus.

2) Retrovirus infects lymphocyte extracted from bone marrow of the patient and cultured 

3) Retrovirus makes a DNA copy of its RNA. This DNA carrying the normal gene inserted into chromosome of host cell.

4) These engineered cell are inserted into patients bone marrow.

5) The lymphocytes subsequently produced by these bone marrow stem cells have fully functional ADA gene. These cells can play normal role in patients immune system. 

BIOTECHNOLOGICAL APPLICATION IN MEDICINE

 Genetically Engineered Insulin

Every single person out of 3 persons living on the plant is suffering from diabetes which is very serious issue that even can cost your life. It is due to some irregularities in the eating habit. 

And many people do not know that diabetes is hereditary that as a parent if you have been diagnosed with diabetes then your child is also at risk.

Diabetes is so risky that according to The National Diabetes Statistics Report 2020 more than 2 lakh children have been diagnosed with diabetes in only united states only. So this is high time we need to do something so for this science has provided us a solution that is "Genetically Engineered Insulin". 

Now let's study about the structure of Insulin 

Human Insulin is made up of 51 amino acids arranged in two polypeptide chains, A having 21 amino acids and B have 30 amino acids. The 2 polypeptide chains are interconnected by two disulphide bridges or S-S linkages. S-S linkages also occur in A chain. Below is the diagram of S-S linkages for better understanding :-

The hormone develops from a storage product called Proinsulin. Proinsulin has three chains A, B and C. C chain with 33 amino acid is removed prior to insulin formation. Bacteria cannot be made to synthesise insulin from its gene because of the presence of introns.

Now let's see how insulin Synthesized ?

Insulin is produced by the Beta cell of the islets of Langerhans of the pancreas. The gene for this protein synthesis is located on chromosome 11. In mammals, including humans, insulin is synthesized as a prohormone like a proenzyme, prohormone needs to be processed before it becomes fully mature and functional hormone which contains an extra stretch called C Peptide. 

This C peptide is not present in mature insulin and is removed during maturation into insulin. The main challenge for production of Insulin using our DNA technique was getting insulin in mature form. In 1983 Eli Lilly an american company first prepared two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of Escherichia coli to produce insulin chains.

Chains A and B were produced separately extracted and combined by creating Disulfide bonds to form Human Insulin 

 

 

Insect Resistance plants !!!

 Can plants be insect resistant ?

So must be you thinking what a joke is going to be explained here, but mind it, it is not joke but reality that is practiced. Read the blog carefully it might change your perception.

So the answer for the question yes one of the example is "BT COTTON".

So have you heard about "BT Cotton" if not then please read the blog below

What is BT Cotton ?

BT Cotton. Soil Bacterium Bacillus Thuringiensis (BT for short) produces proteins that kills certain insects like lepidopterans (tobacco budworm, armyworm), Coleopterans (beetles) and Dipterans (Flies, Mosquitoes). Bacillus Thuringiensis form some protein crystals. These crystals contain a toxic "insecticidal protein"

Why does this toxin not kill the Bacillus (Bacterium)?

The BT Toxin exist as inactive protoxins but once an insect ingest the inactive toxins it is converted into an active form of toxin due to Alkaline pH of alimentary canal that solubilizes the crystal.  

The activate toxins binds to the surface of midgut epithelial cells and create pores which cell swelling and lysis and finally death of the insect.

How BT Cotton is made ?

BT Toxin genes were isolated from Bacillus Thuringiensis and incorporated into various crop plants like cotton. The choice of genes depend on the type of crop and targeted pest as most BT toxins are insect group specific. 

The toxin is coded by a gene named cry. There are number of genes, cry IAc and cry II Ab have been incorporated in the cotton. The genetically modified crop called BT Cotton as it contains BT Toxin genes. Gene cry IAc and cry II Ab control cotton bollworm and cry IAb protect the same from corn borer.

Rice of golden color ???

 Golden Rice

Many of us might think that this is a joke or trick for click bate but the reality is that there is a vitamin A enriched rice called "GOLDEN RICE" 

scientific Classification

HISTORY OF GOLDEN RICE

In late july 2008 Adrian Dubock approached asian institute of management with some Golden rice marketing research planned for 2009, the idea was to involve Golden rice humanitarian board member and prof of marketing in providing a seminar of MBA student to focus on group management and analysis followed by a month of engagement to train students for conducting the focus groups and replying back. 

 GOLDEN RICE AND ITS BENEFITS

Golden rice is a transgenic variety of rice (Oryza Savita) which contains good quantities of β-carotene (Provitamin A that is inactive state of vitamin A).β-carotene is a principle source of Vitamin A. Since the grain seed are yellow in color due to presence of β-carotene the rice is called "GOLDEN RICE"

β-carotene is converted into Vitamin A. Thus golden rice is rich in vitamin A. It is required by all individuals as it is present in retina of eyes. Deficiency of Vitamin A causes night blindness and skin disorder.

So the question arises why we should use Golden rice instead of using Normal rice ?

 

So the answer to this question is that you should use golden rice instead of normal rice because contents of Vitamin A are in lower content as compared to Golden Rice which have rich Vitamin A content because of presence of β-carotene which is precursor of Vitamin A. 

Prof Ingo Potrykus and Peter Beyer produced a genetically engineered rice by introducing three genes associated with synthesis of carotene. The grains of rice are rich in provitamin. 

Is Human cloning practiced ???

The answer to your question is clearly NO !!! But the next question that arises in everyone's mind is WHY ??? Today we w'll give answer to this question. 

ETHICAL ISSUES OF CLONING

WHAT ARE ETHICS OF CLONING ?

Morals of cloning alludes to assortment of moral position with respect to practice and conceivable outcomes of cloning particularly Human cloning. While a large number of these perspectives are strict in cause, Some of the inquiries raised by cloning are looked by common points of view too.

In some countries laws have been made regarding cloning to ensure safe and healthy way to use these biotechnological processes. Advocates related to these cases have proposed usage of these kinds of techniques for only welfare or for treatment of various kinds of genetic disorder only.

It all started back in 1963  when one of the most important research was going on and soon enough first successfully cloned sheep named Dolly was created. Though it may look a useless experiment to some but mind it, it was the beginning of a new era in the field of biotechnology where we would have answer to many hidden secrets that we still want to find.

 But cloning never was nor it would be a "SAFE PRACTICE TO FOLLOW"

Human cloning possible or not ?

What is cloning ? 

Cloning is the process of producing individuals with identical or virtually identical DNA, either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments.

HUMAN CLONING

Human cloning is the creation of a genetically identical copy (or clone) of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissue. It does not refer to the natural conception and delivery of identical twins. The possibility of person cloning has raised controversies.

 

History of human cloning

The building blocks of human cloning was laid by J.B.S.Halden. He introduced the idea of human cloning for which he used the term clone. In 1963 he gave a speech on the biological possibilities of human species of next 10,000 years at Novartis foundation (known as Ciba foundation) in which he said 

"It is extremely hopeful that some human cell lines can be grown on a       medium of precisely known chemical composition. Perhaps the first step will be the production of a clone from a single fertilized egg. Assuming that cloning is possible, I expect that most clones would be made from people aged at least fifty, except for athletes and dancers, who would be cloned younger. They would be made from people who were held to have excelled in a socially acceptable accomplishment."

The first successful cloning experiment led to the  successful  production of a cloned sheep named as "Dolly" in 1996 by the technique called SCNT (Somatic Cell Nuclear Transfer). 

The first Hybrid human clone was created using the same technique that was used to create "Dolly" that is SCNT but the effort was soon destroyed. Nucleus was taken from man's leg cell and was introduced in a cows egg cell but the embryo was destroyed after 12 days of observation, this was due ethical implication associated with cloning which will be talked about in later paragraph.

How was cloning done ?

There are many techniques for cloning a human but the most commonly used techniques is SCNT (Somatic Cell Nuclear Transfer).

SOMATIC CELL NUCLEAR TRANSFER

This technique involves isolation of egg cell and cell with desired set of genes. Nucleus is isolated from the cell with the desired set of genes this is done because the genes are present in DNA and DNA is embedded in nucleus. Nucleus is isolated from the egg cell and kept aside. We do not  require nucleus from the egg cell so as to avoid mixing of genes. The nucleus from the cell of desired genes is embedded in the cell aperture so as to provide nourishment.

The cell thus obtained is cloned via two methods :-

1) Reproductive cloning - In this technique the cell obtained from the above procedure is transferred for surrogate mother for growth and development of the cell 

2) Therapeutic cloning - In this technique the cell obtained is transferred to a cell culture for growth and development of cell. 

  

 conclusion

We would conclude by saying that human cloning is possible but in the next Blog we would discuss that why it isn't practiced today?