BT501 Midterm Current Subjective by Biotech Brainy Bunch

BT501 MIDTERM SUBJECTIVE

BY MEHWISH MUGHAL

Hemophilia and genetics.

It has been reported that the Arab physician Abu al-Qasim al-Zahrawi, commonly known as Abulcasis, wrote a book on hematology. His book Al-Tasrif written during the period 1000 AD provided the first description of hemophilia, a hereditary genetic disorder

Hemophilia is a hereditary bleeding disorder resulting from a partial or total lack of an essential blood clotting factor. It is a lifelong disorder that produces excessive bleeding, and spontaneous internal bleeding occurs very frequently. Hemophilia A, the most common form, is caused by a deficiency in clotting factor 8 (factor VIII). Hemophilia B results from a deficiency in clotting factor 9(IX). This disorder is inherited in a sex linked recessive manner.

Parkinson's disease and its conditions.

After Alzheimer disease, Parkinson disease is the second most common neurodegenerative disease. Parkinson disease affects about 1% of the population that is 60 years of age or older and is characterized by the progressive reduced capacity to initiate voluntary movements arising mainly from the loss of neurons that synthesize the neurotransmitter dopamine. Among the many factors that mediate the development of Parkinson disease, mitochondrial dysfunction is considered to be a major factor in its etiology and pathogenesis.

The dysfunction of mitochondria in Parkinson disease patients may result from one or more of the following conditions:

•  Deletion of mitochondrial DNA,
•  Accumulation of mitochondrial DNA
•  Mutations, increase in oxidative stress from reactive oxygen species
•  Deficient expression and function of the mitochondrial respiratory chain
•  Abnormal morphology of mitochondria.

Neurodegenerative diseases such as Parkinson disease are often closely associated with an imbalance of mitochondrial homeostasis. The levels of many mitochondrial proteins are altered in postmortem samples of brains from persons with Parkinson disease. Genetic mutations in the PTEN-induced putative kinase 1 (PINK1), parkin (PARK2), DJ-1, alpha-synuclein (SNCA), and leucine-rich repeat kinase 2 (LRRK2) genes are closely linked to the recessive Parkinson disease genes. Moreover, these mutations are associated with important functions that maintain mitochondrial homeostasis, which include membrane potential, calcium homeostasis, structure of cristae (internal compartments formed by the inner membrane of mitochondria), respiratory activity, mitochondrial DNA integrity, and clearance of dysfunctional mitochondria from cells.

Cardiovascular diseases.

Major cardiovascular diseases include several subtypes, such as coronary heart disease, cerebrovascular disease, heart failure, rheumatic heart disease, and congenital heart disease. Cardiovascular disease is a leading health problem, affecting more than 80 million individuals in the United States. In Canada, 1 out of 3 deaths is attributable to cardiovascular disease.

The major risk factors associated with cardiovascular diseases are cigarette smoking, unhealthy diet, physical inactivity, hypertension, diabetes, and high blood cholesterol. Cardiovascular diseases may also result from a variety of genetic causes, including singlegene mutations, interactions between multiple genes, and gene–environment interactions.

Economic shifts, urbanization, industrialization, and globalization bring about lifestyle changes that promote heart disease. In developing countries, life expectancy is increasing rapidly and is expected to expose people to these environmental risk factors for longer periods.

Nanobiotechnology and it's applications

Explain RNAi mechanism of Gene expression

The RNA interference (RNAi) is a natural process that cells dictate to turn down or go to a silent state; such activity cell is regulated by a specific gene known as RNAi. The RNAi technology provides excellent tools to study the role specific gene in the development, causes, and progression of particular diseases, and has taken the biomedical community by storm. It has been reported that RNAi was first noticed in the plant Petunia when plant biologists tried to develop the purple color of the flower by introducing a pigment-producing gene. Surprisingly, the gene which was introduced to intensify color in the plants was found to suppress the color. In the end the resulting flowers developed white patches or became completely white. Surprisingly, a few years later another group of researchers observed a similar kind of gene-silencing effect in Caenorhabditis elegans.

Later on, it has been reported that the gene-silencing effect is caused by the presence of doublestranded RNA, and this double-stranded RNA is normally not found in healthy cells. RNAi technology has been in use in various fields of biotechnology, particularly in the food plant engineering that produces lower levels of natural toxins. No plant that uses RNAi technology has yet passed the experimental stage; however, research work has been known to effectively reduce the allergen levels in tomato plants and also is known to cut the cancer causing agents in tobacco plants. Also, other plant characters that have also been bioengineered include the production of nonnarcotic natural products by using the opium plant, development of resistance to common plant viruses, and protection of plants with dietary antioxidants. Interestingly, bioengineered plants such as FlavrSavr tomatoes and two cultivars of ring-spot-resistant papaya were originally developed by employing antisense technology. One of the pronounced applications of RNAi technology is its application in medicine. Over the past few years, efforts have been made to understand RNAi„s role in normal and diseased cells, and also to use the RNAi technology for use in medical therapies. It has been suggested that human disease progression can be blocked by using RNAi-based therapies to turn down the activity of genes.

Cancer, for example, is frequently caused by over-excited genes in the cells, and retarding their activities could stop the disease progression. Over the last few years, several pharmaceutical companies are using RNAibased therapies to treat for various forms of cancer. In addition, viral infections can also be treated using RNAi-based therapies and this can be done by reducing the activity of key viral genes. It has been shown in the laboratory that human cells have successfully stopped the growth of HIV, polio, hepatitis C, and other viruses in human cell culture and RNAi-based therapies against HIV are under clinical trial stages.

Moreover, the importance of RNAi technology has some beneficial effects in finding out the cause of the disease. Using RNAi technology, the activity of a particular gene can be knocked down which will help us to understand its role in the disease development and progression. For many years, researchers have been studying how proteins regulate gene activity. Now with the help of RNAi technology, it would be possible to discover the role of proteins in gene regulation.