DNA repair

The process by which the cell identifies and repairs the damages done to the DNA molecules is known as DNA repair. DNA damage can be caused due to normal metabolic activities or environmental factors like Radiations or Ultra-Violet light. This results in the molecular lesions as many as 1 million per day. There is a high possibility that the lesions cause structural damage to the DNA molecule and they can also modify or eliminate totally the ability of cell to transcribe the gene that affected the encodes of DNA.

Several other lesions are harmful for the mutation of the genome of cell and this affects the survival of its daughter cell after undergoing the process of mitosis. The process of DNA repair is carried out constantly as it responds continuously to the damage in structure of DNA.

Extra cellular environment, age of cell, type of cell are some of the factors on which rate of DNA repair is dependent. Any cell which has a large amount of DNA damage or it can no longer be effectively repaired, such cell enter the following 3 stages

• Senescence, which is stage of dormancy and it is irreversible
• programmed cell death, apoptosis which is also known as cell suside
• unregulated division of cell which finally leads to serious health problems like cancer and tumor

The DNA repair ability is very important to integirty of the genome of the cell. It is very essential that the DNA repairing fuction is carried out smoothly for the normal functioning of that organism.

Gene therapy

Genes are carried on the chromosomes and they are the basic functional and physical units of hereditary. Genes provide the guidance for specific sequences of the basis which encodes instructions of making proteins. Even thought gene get vital attention the key role is played by the proteins, which perform most of the life functions and is also responsible for number of cellular structures. But in case if the genes are altered, proteins cannot perform their normal functions and may result in genetic disorders.

Gene therapy provides various ways and means for fixing the genetic disorders or defects. There are number of approaches which can be used by Gene therapy. Depending upon the type of disorder the most suitable approach is adopted generally. Following are some of the common approaches adopted by the research teams:

An insertion of the normal gene is done in the non specific location within genome to replace the non functional gene.

The normal gene can be replaced in place of some abnormal gene via the homologous recombination

With the help of reverse mutation, the abnormal or the defective gene can be repaired by which it can return to its normal gene functions.

There can be modification done in the regulation of the particular gene.

Multifactorial Disorders

It is studied by researchers that a genetic component is responsible for most of the diseases and conditions in human beings. Some disorders like the cystic fibrosis or the sickle cell anemia are a result of mutations in a single gene. However, the cause of many other diseased conditions is very complex. Some of the common disorders like diabetes, heart disease and obesity are not a result of a single genetic cause, but they are caused due to the result of multiple genes, in combination with the environmental factors as well as the lifestyle of the person. Multifactorial Disorder is caused by the interaction of genetic and non-genetic factors along with the environmental factors.

Multifactorial Disorders are frequently seen clustering in families, but they do no have a well-established pattern of inheritance. Thus, it becomes difficult to determine whether a person is at risk to inherit or pass on this disorder to the next generation. Multifactorial Disorders are very complex, hence difficult to treat as well as study as the particular factor responsible for most of these disorders are not yet identified.

There are many common diseases seen running in the family, but the simple inheritance pattern of a single gene disorder is seen lacking there. These Multifactorial Disorders includes diseases like epilepsy, manic depression, asthma, schizophrenia and hypertension. Some of the developmental abnormalities also come under this category like the cleft palate, neural tube defects like spina bifida and congenital heart defects.

The Multifactorial Disorders have a very low heritability in comparison with the single gene disorder. For instance: only 5-7% of your close relatives or family members of diabetics suffer from the same disease, and lower would be the case for single gene disorder such as cystic fibrosis. This clearly states that a single genetic factor is never responsible to cause diseased conditions in your body. There are a number of genes that combine along with the environmental factors like exposure to hazardous chemicals or poor diets, which cause disorders in a person.

The occurrence of the Multifactorial Disorders is thought to be dependent on the balance of risks. There exists a balance between the variants of genes with positive as well as negative effects, and between environmental factors again with positive as well as negative effects. Too many negative factors, both environmental and genetic may tilt the balance towards various disorders.

In a Multifactorial Disorder, sometimes the risk may depend on the sex of the affected person. For instance, pyloric stenosis is a Multifactorial Disorder occurring five times more often in males as compared to females. If a female suffers from pyloric stenosis, her as well as her parent's risk of having other child affected with this condition will be higher than if a male child would be suffering with it. The occurrence of this condition in females has a higher genetic liability apparently, a number of abnormal genes are isolating in the family.

Thus, we can shortly state that there is a similar risk for the first-degree relatives such as parents, siblings or offspring's to develop Multifactorial Disorder. The severity of the disorder and the sex of the person can play a role in modifying the risk. Some of the common chronic diseases are Multifactorial Disorders of the genes. The conditions with Multifactorial Disorder include cancer, birth defects, coronary artery diseases and mental disorders.

Gene Mutation

Any permanent change in the structure of DNA sequence which makes up a gene is called as gene mutation. The size of the mutation varies , it may either as small as a DNA or even large as a segment of the chromosome.

The mutation of the Gene occurs in two ways: 1. from a parent 2. acquired during the persons lifetime. Hereditary mutations or the germ line mutations are those which occur from the parents to the children. The mutation of this sort can be seen in the persons entire like in every cell in his/ her body.

The other are the new mutations which are occurred in the egg or the sperm cell or the mutation which occurs just after the fertilization process is complete. The genetic disorders can be best explained by the De novo mutations, however in this type of disorder there is no family history for this disorder involved.

The somatic (also known as acquired) mutations are the one which occur directly into the DNA of the individual cell. There is a possibility of DNA making copies of itself during cell division due to immense expose to the ultra violet radiations from the sun which result in number of changes in the individual's life. The acquired mutations int he somatic can not be passed to the next generations.

Mutations can also occur in the single cell in the early period of embryo. During the division of the cells the individual has some cells with the mutation and some other without any genetic changes. This situations is referred as mosaicism.

Some of the changes in the genetic makeup of the cells are very rare to find, while on the other hand some changes are easily spotted. The Genetic changes which can be found in more than 1% of the population are known as polymorphisms. polymorphisms are resposbile for the differences like the color of the hair, blood type and the color of the eye. Usually, polymorphisms don't have any negative effects which affects the health of an individual, however they may also cause number of variations which can develop certain disorders in the individual.

How safe is your Salad?

Salmonella bacteria



According to research around 80 million people in US are affected by food poisoning by food borne diseases every year. Bacteria are the most common cause for food borne. According to recent studies, there is a possibility that the bacteria contaminates all types of meat and number of food products.

On some new channels there are announcements made for fighting against the microbial food contamination. Salmonella bacteria are one of the major source which contaminate the salad leaves and other vegetables. Flaggela is used by the Salmonella bacteria for attaching the lettuce leaves. According to genetic researches if the vegetables are to free from such harmful contamination they should remove the flaggela with genetic engineering tools and techniques. Now, that the prime focus of the researchers is to remove the Salmonella bacteria for safe and healthy food.

Dangers in genetic engineering

Genetic engineering has number of positive sides but as they say coin has two sides, likewise genetic engineering also has some following dangers

• While transferring of one gene to other there is a possibility that the function of the other gene may get disturbed and it can cause adverse affect to the life of the organism.

• The scientists perform the surgery of the DNA without properly understanding the mutations which are involved in it. These mutations can be harmful to our health and indirectly it will affect the environment.
  

• In genetic engineering number of materials are used which are not the part of the human food supply and since there is no long term testing of this food materials , there is a possibility that it may affect our health.

• There is a possibility of generating a high level of toxins in the food as genetic engineering can cause unexpected mutations in the organism which eventually will generate high amount of toxins.
  

• It is impossible to recall the genetic engineering bacteria, organisms or the viruses. This may lead to serious health problems to all the living creatures on the Earth.
  

Genetic engineering

The laboratory technique used to change the DNA of the organisms is known as Genetic engineering. The individuality of the organism is known from its DNA. The biochemical process in the organisms helps the organism to store the in the DNA. DNA is the main player in the health, growth and the life of the organism. Genes are the specific features and functions which are which are associated with the DNA.

According to Molecular Biologist, DNA structure can be changed by number of enzymes. Some of the enzymes can also join or cut the strands of the DNA structure. With the help of enzymes, the scientists cut down the genes from the DNA and customize the DNA by the help of genes. The scientists believe that with the help of genetic engineering they can improve number of things like the quality and the standards of the food we eat, survival of the fish in very cold waters and many more things.

So, the in shorter terms genetic engineering reefers to the modifications (changes) made in the DNA by using advanced technology.

Genetic disorders and types of genetic disorders

What are genetic disorders?
An abnormality in the DNA or any genome individual cause the genetic disorder. The abnormality can be caused due to several reasons like subtraction of the set of chromosome or even a single chromosome, it can also be caused due to small mutation of the gene etc.

The following are the four main types of genetic disorders:

1) Monogenic or single genetic disorder: The changes which occur in the DNA sequence causes monogenic disorders. Most vital functions o the life are performed by the Genes code for proteins and they constitute a major proportion in the cellular structure. The protein of the gene cannot carry a normal function if the gene is mutated.

2) Complex or Multi factorial: mutations in the multiple genes and the combination of the environmental factors causes the Complex or Multi factorial disorder. As, the name suggests it contains number of genes which makes it more complex disorder than the monogenic disorder. Multi factorial, is one of the most common disorder.

3) Chromosomal: Each cell has a nucleus which contains the Chromosomes which are the structures made of protein and DNA. Chromosomes are the main carriers of the genetic material any abnormality in the chromosomes causes Chromosomal disorder. Microscopic examination help to detect the major abnormalities taking place in the chromosomes. trisomy 21 or the Down syndrome are some of the commonly observed abnormalities due to copies of chromosomes.

4) Mitochondrial: Mutations in non-chromosomal DNA of the mitochondria causes the Mitochondrial genetic disorder. cellular respiration is the main function of the mitochondria, if any disorder in the functioning of the mitochondria can cause serious disorders.
Pattern of the Mitochondria

Human Genetics

The study of human inheritance is known as human genetics. Human genetics helps to understand the human behavior, human nature, understand the diseases and understand the genetics of human being.


Patterns of Inheritance patterns and Genetic differences



A Karyotype



The human Karyotype
The human genome contains 2 sex chromosomes and 44 autosomes which sum up to 46. During the meta phase of meiosis the pictures of homologous chromosomes which are linked together are known as Karyotype. So in all there are 46 Karyotype in normal Human being.


Pedigrees

The transmission of the genetic traits over several generations is showed systematically by a diagrammatic representation known as Pedigree. Genetic disorders or diseases can be easily spotted with the help of pedigree. Autosomal dominant, x-linked, autosomal recessive and the y-linked are the different traits which can be analysed with the help of pedigree chart. Pedigree also help to calculate and show the Partial penetrance. Almost of the genetic counselors for genetics make the use of Pedigree for determining the hereditary disorders.

Autosomal Dominant Inheritance

The Autosomal traits are associated with a single on the auto some and they are also refereed as dominant as they are single. They are enough for appearance of a single trait. One of the parent must have the same trait.

Autosomal Recessive Inheritance

It is one of the pattern for a trait or a disease which can be passed through families for generations and generations. For displaying of this trait it is essential to the presence of have two copies of trait or disorder. The location of the trait or gene is found on the non-sex chromosome.

DNA

DNA is a biological material that enables an individual to be identified against any other individual anywhere in the world. It is the most effective subject for determining whether two or more individuals are biologically related, and it is of vital importance in solving crime and determining paternity. But most people don’t know a great deal about what DNA actually is, how it works and why it is the subject of so much research and so much development spending.

DNA, or Deoxyribonucleic acid, is a material found in us all, profiling what we’re like and where we’ve come from. It’s passed down to us from our parents, where we receive half of our DNA maternally and half our DNA paternally. The DNA itself contains the instruction or blueprint for life, and controls the function of the cells as well as being a perfect indicator of ancestry and biological relations.

DNA is made up of various nucleotides, and is essentially made up of amino acids, and it is matched with the so-called bases which provide the key to determining the genetic blueprint. DNA can be extracted from a range of sources, including samples of hair, cigarette butts, blood, razor clippings or saliva. Thus it is relatively easy to obtain samples, which can then be tested in a laboratory to determine any genetic relationships that may be present.

Deoxyribonucleic acid, DNA, which makes up the genetic material in cells, is comprised of units called nucleotides.

Nucleotides can be simply described as the nutritional building blocks of new cells. There are five key nucleotides, which form the crucial building blocks of DNA and RNA, and are therefore essential for ongoing new cell production and system repair.

The body has an ongoing demand for new cell production, and must create cells at the same rate at which its cells die. To do this, a typical cell must double its mass and duplicate all of its contents in order to produce the two new ‘daughter’ cells.

This multiplication of a cell starts with the doubling of the information (inter-phase) - namely the DNA. Previously we discussed how the DNA is formed by the five key nucleotides. A normal DNA consists of 3 billion nucleotides.

It is only after this multiplication of the DNA that the M-phase can start. This is where the two cell nuclei are formed and the cells start to divide into two separate cells.

Cell proliferation is a lengthy and complicated process, dependent mainly on energy and supply of the specific building blocks, the five key nucleotides.

Research has shown that by providing extra dietary sources of nucleotides, the multiplication of these new cells can be speeded up. This applies to the following cell types:

Intestinal mucosa cells – the cells lining the gut

Bone marrow cells, namely leukocytes (especially Lymphocytes) – more commonly termed as the white blood immune cells

Erythrocytes – Red blood cells

Certain brain cells

For years, nucleic acids and nucleotides were considered essential nutrients. Now these nucleotides are increasingly considered to be limiting in certain diets and during periods of stress and illness.

It was thought that the body could synthesise sufficient nucleotides to meet its physiological demands via ‘de novo’ synthesis of nucleotides. However, research during the last several years indicates that this is not correct. There are certain conditions in which the body requires dietary nucleotides to meet its physiological requirements.

These conditions include:

Rapid growth

Limited food supply

Stress

Chronic disease

Bacterial and viral infections

In these situations, metabolic demand exceeds the capacity of the ‘de novo’ synthesis, and therefore dietary nucleotides become conditionally essential.

Importantly, dietary nucleotides may also spare the energetic costs of ‘de novo’ synthesis of nucleotides.

Critical point in nutrition: energy

Building nucleotides by the ‘de novo’ process requires lots of time and energy. Supplementing purified nucleotides to the diet reduces the proportions required to manufacture, while accelerating all active processes and saving energy also.

Supplementary nucleotides have been demonstrated to enhance the efficiency of a number of vital organs; these include:

Immune organs including the bone marrow

Liver

Intestines

Consequently, supplementary nucleotides have an effect on a number of vital functions:

Immunity

Production of stress hormones

Digestion and absorption of nutrients

Vitality and well-being

Focussing on Immunity

Nucleotides are an essential part of an healthy immune system, because they have been shown to support the following:

The reversal of malnutrition or starvation-induced immunosuppression

Enhancement of T-cell maturation and function

Enhancement of natural killer cell activity

Increase of delayed cutaneous hypersensitivity

Aiding resistance to infectious agents such as Staphylococcus aureus and Candida albicans

Modulation of T-Cell responses toward type 1 CD4 helper lymphocytes or TH1 cells.

In layman’s terms, nucleotides help to boost the immune system by speeding up the process of creating new defence cells, which are essential for the body to fight infections.

Reducing the effect of an infection

In 2003 a double-blind placebo controlled trial was carried out by Dr Isobel Davidson at Queen Margaret University College, Edinburgh. This clinical trial was carried out to test the effects of nucleotides on reducing the severity of specific symptoms, secondary infections and healing time after a natural infection by the cold or flu virus. The findings showed that the specific formula of nucleotides significantly reduced the symptoms of painful sinuses and earache. Over the first six days of taking the nucleotides or a placebo, the discomfort level was on average greatly reduced for the nucleotide patients:

Dry mouth: 30% less

Sore throat: 20% less

Muscle aches: 15% less

Headache: 40% less

Salivary IgA (antibody) concentrations were similar at recruitment, but the subsequent to this were higher in general for the nucleotide group. For the layman, higher antibody levels indicate a greater immune response.

Preserving a strong immunity

The positive effects of supplementary nucleotides on immunity was also backed up with another placebo controlled trial carried out by Professor Lars McNaughton, University of Bath, 2002. McNaughton tested the effects of nucleotides on athletes under both short-term and high intensity, and moderate endurance exercise. Again these results were significant and conclusive. Athletes on the nucleotide treatment showed a 25% higher IgA concentration after 90 minutes endurance exercise, compared with the placebo group.

The stress hormone, cortisol, was 10% reduced for the nucleotide supplemented group. High cortisol levels have been shown to impede the effectiveness of disease fighting cells. Hence, the placebo group showed a greater drop in antibodies. High decreases in IgA (antibodies) are thought to be a reason for increased levels of Upper Respiratory Tract Infection (e.g. colds and flu) for athletes and people suffering high levels of stress.

In conclusion, the body needs nucleotides to help support a healthy immune response. The body can normally take these from food, but in times of stress, illness, poor diet or rapid growth, dietary nucleotides become conditionally essential; supplementing all five nucleotides has been shown to preserve a strong immunity, and reduce the severity of infections.

Genetics- An introduction

Genetics is one of the main streams of biology. It is also known as the science of variation and hereditary in the living organisms. The method of selecting breeding was discovered due to the fact that the living things are inherited from their parents. In the mid of the nineteenth century modern science of genetics started a research on the process of inheritance under the leadership of Gregor Mendel.

Genes corresponds to the regions within the DNA, which comprises of different types of nucleotides and the sequence of this nucleotides contain the genetic information of that organism. DNA is found in the double stranded form and the nucleotides of each strand are complementary to each other. A new partner can be created from the each strand which indirectly plays the role of a template.

Chains of amino acids creating the proteins are created by sequence of nucleotides in the gene translation done by cells. The order of nucleotides in the gene is corresponds to the order of the amino acids in a protein. This is popularly known as the genetic code. The amino acids found in proteins decide how to fold into a 3D shape and this structure is responsible for the function of protein. For the cells to survive the major functions for their survival are carried out by the proteins. protein's amino acids can be changed if there is a change of DNA in a gene. Also, the functions and shape are changed drastically along with it and it directly affects the life of the organism.

The combination of genetic is the major factor which ultimately decides the outcome in the organism. example the height and health are the factors determined by the genes in childhood and the outcome can be seen in the later years as well.