Question

5-10

6. What is gene therapy? Give an example of how has been wed. What are some difficulties encountered with its use? 7. What is DNA profiling and how is it used in forensic investigations 8. Why is it easier to determine innocence than guilt using DNA profiling? 9. What is genomics and how does it provide insight into evolution? 10. In what year was the complete sequence for the human genome achieved? What percentage of the human genome codes for proteins, tRNA and rRNA?

Answer 1

Recombinant technology used to improve nutrition of crops and animals

In plants:

· Iodine containing crop may be produced by incorporating gene that enhance iodine uptake. Like hNIS protein in Arabidopsis thaliana.

· Fortification of food crops, like increasing folate, as induced in tomatoes, by overexpressing genes encoding enzymes for folate precursors.

· Biofortification with iron to cope with anemia. This is done by reducing the effect of phytase, that act as inhibitor of iron absorption.

· Crops with higher nutritional values like higher protein levels may be made to cope with malnutrition.

· Certain crops may be enhanced using biotechnology to alter them as drought resistant, frost resistant, crops growing under acidic soil, water-logged condition, extreme temperatures. Thus, crops may be grown in poor optimum condition and area that were unsuitable for agriculture.

· Biotechnology may be applied to produce insect-resistant, pest resistant, virus-resistant crops. Like Bt (Bacillus thuringiensis). This regulates the use of insecticides, pesticides. Also, lesser crop waste occurs due to fewer infections.

               In Animals

· Introduction of gene bovine Somatotropin (bST) to increase milk production.

· Biotechnolgy applications in animals are limited due to ethical reasons.

Genetic testing:

A specific mutation in genes, chromosomes, or proteins; in form of changes during inheritance, may be neutral (with no effect), beneficial or harmful. These inherited changes, may be detected by genetic testing. Inherited alteration in a person’s genome may be potentially harmful, when they may be factor for diseases running in a family.

In such cases, genetic testing may be applied to detect DNA, RNA, or protein of an individual, to observe and analyze:

1. Genetic mutation

2. Genotypes related to the disease

3. Phenotypic alterations

4. Karyotypes.

Genetic testing or testing may be done for:

· Testing of newborn-early stage detection of any genetic defect or carrier of mutated genes may be detected in newborns. Beneficial to detect congenital defects.

· Parental testing: Prospective parents may be screened to detect any mutation that may pose a problem to offspring.

· Diagnostic test: If a disease is running in the family like FAD (Familial Alzheimer Disease), diagnosis may be obtained even when individual is asymptomatic or an early diagnosis before onset may help in pre planning precautions and treatments.

· Pre-implantation test- detection before implantation, such as in case of in vitro-fertilizations.

· Forensic studies- Detection of DNA for legal purposes.

Example: Considering an autosomal dominant genetic disease which is caused by mutation in a single copy of gene form a parent in a family. This disease is referred to as e FAD or early onset of Familial Alzheimer Disease.

If genetic testing is done (even when the individual is asymptomatic), it will help in detection of the presence of e FAD gene, how it may affect in near future, weather the defect will be present in the progeny.

Thus,

a. To contribute to the progression of genetic medicine

b. Its prospect in revealing the future scope of a disease that may occur,

c. Their possible prevention (if other factors, like diet, medications, environment) can reduce the occurrence or severity of the disease,

d. To determine the treatment that is possible,

Companies:

· 23 and me

· Color genomics

· Gene by gene

· Laboratory corporation of America

· My Med Lab

Advantages

Importance of early detection: Early detection is important as-

1. The presence of an inherited defect, causing a disease at a certain age or in future, may be detected early.

2. Take a clinical point of view regarding the seriousness or effect of the disease, like in case of cancerous genes.

3. Further tests and diagnoses to performed and initiate early treatment of the disease. This may also help in early trials of the medications, interactions and side effects of drugs, hypersensitivity analysis).

4. To be mentally (to cope with the symptoms and treatment) and practically (like insurance for the family, will etc.).

5. To know the heritability prospect of the disease in progeny. This will help them to decide regarding marriage or family planning.

6. Some diseases may be further affected due to other factors, like environment, diet, and other medications. Those complications may be avoided.

Disadvantages

The problems are:

1. Since, the testing is based on predictive diagnosis, there may be question in its practical aspect, regarding the real prospect of the disease in future.

2. The test, diagnoses, treatment plan may change in future (during the disease occurrence), due to new research, methodologies, scientific progress. This will make the early genetic detection almost useless.

3. The emotional condition of the individual may alter after knowing about the future prospect of a disease (which might not occur, due to a condition). This may lead to depression, anxiety disorder, and other mental and psychiatric conditions, affecting the normal life.

4. Family support or interactions may decrease after knowledge of a disease, in an individual.