Unit Title: Biochemistry Of Nucleic Acids.(A.C. 5.1 And

Cancer is a genetic disease caused by certain changes to genes that control the way our cells function, especially how they grow and divide. Genes carry the instructions to make proteins, which do much of the work in our cells. Certain gene changes can cause cells to evade normal growth controls and become cancer. Genetic changes that promote cancer can be inherited from our parents if the changes are present in germ cells, which are the reproductive cells of the body (eggs and sperm). Such changes, called germline changes, are found in every cell of the offspring. In general, cancer cells have more genetic changes than normal cells. But each person’s cancer has a unique combination of genetic alterations.

Heredity also plays a role in the development of cancer. If a person’s relatives have a history of cancer, then that person has a higher risk of developing cancer. Genetic variations, particularly those influencing how the body responds to carcinogens, may create a greater vulnerability to cancer.

Frame shift mutations are the type of mutation caused by the addition or deletion of a base pair in the DNA resulting in the translation of the genetic code in an unnatural reading frame from the position of the mutation to the end of the gene. In the mutations, we added and deleted beads resulting in an incorrect sentence that does not make sense.

level? A mutation in just one allele of proto-oncogenes can cause over production of cells tumor, and thus tumor formation, because they are dominant. Tumor suppressor genes require mutations of both alleles to inhibit function because they are recessive.

Each human being has something called DNA. DNA is described as genetics and an extremely long macromolecule that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms. DNA constructs of two nucleotide strands coiled around each other in a ladder like arrangement with the sidepieces composed of alternating phosphate and deoxyribose units and the rungs composed of the purine and pyrimidine bases adenine, guanine, cytosine, and thymine. Each chromosome consist of one continuous thread-like molecule of DNA coiled tightly around proteins and contains a portion of the 6,400,000,000 basepairs that make up your DNA.

Our genes regulate cell growth and cancer occurs due to abnormal changes in these genes. Genes are in each cell's nucleus and control the cells growth in relation to our genetic make up. The cells grow and replace themselves in a natural

These mutations can be due to an error in DNA replication or due to environmental factors, such as cigarette smoke and

By helping to repair DNA, the BRCA2 protein plays a critical role in maintaining the stability of a cell 's genetic information. The cancer risk caused by BRCA2 mutations is inherited in a dominant fashion, even though usually only one mutated allele is directly inherited. This is because people with the mutation are likely to acquire a second mutation, leading to the dominant expression of the cancer. A mutated BRCA gene can be inherited from either parent. Because they are inherited from the parents, they are classified as hereditary or germline mutations. Because humans have a diploid genome, each cell has two copies of the gene (one from each biological parent). Typically only one copy contains a disabling, inherited mutation, so the affected person is heterozygous for the mutation. If the functional copy is harmed, however, then the cell is forced to use alternate DNA repair mechanisms, which are more error-prone. The loss of the functional copy is called loss of heterozygosity (LOH). Any resulting errors in DNA repair may result in cell death or a cancerous transformation of the cell.

complex disease since it affects various parts of the body. The gene mutation causes a defect of a

Breast cancer is the most common cancer that affects women in the United States. There are at least two majors genes (BRCA1 and BRCA2) that when they mutate can cause breast cancer. These genes can be passed from parent to child, increasing the risk of developing cancer in those child that have parent carrying these genes. BRCA1 and BRCA2 genes are located on chromosome 17 and chromosome 13 respectively. There is a 90% chance of developing breast cancer for a woman that has these mutated genes. In contrast, men carrying BRCA1 have no risk to develop breast cancer, but those carrying BRCA2 genes have high risk. It is important to note that mutations in these genes can be passed on to children by either parent. A man with a mutation is just

While there are several biological factors that have the ability to lead to cancer, genetics is the most currently researched. A study done by Bharaj, Scorilas, Giai and

An ordinary human body contains approximately one trillion cells and precisely 46 chromosomes in each cell. However, the human body can be altered by a genetic mutation. Over the course of history, genetic mutations have had a large impact on the human race. They have brought harm to numerous amounts of people. Cancer, in particular, is one of the most lethal diseases. Cancer begins when a portion of DNA inside a chromosome is damaged, causing a cell to mutate. Then, the mutated cell reproduces multiple times and creates a tumor. Afterwards, cancer cells break off of the tumor, enter the bloodstream, and disperse throughout the body. If the cells break off, the tumor is considered malignant - this type of cancer is very difficult to cure.

This was because nucleotide alignment does not consider the repetition of codons of amino acids as is the case with protein alignment, where the amino acids are utilized for sequencing.

Deletion Mutation: is a type of gene mutation wherein the deletion of nucleotides causes a shift in the reading frame of the

Over a lifetime our DNA can undergo changes or ‘mutations’ in the sequence of bases; A, C, G and T. A mutation is a change that occurs in your DNA sequence, either due to mistakes when the DNA is being copied or as the result of environmental factors.Mutations are essential for evolution to occur because they increase genetic variation. Mutations can occur during DNA replication if errors are made and not corrected in time. The mutation can have a positive or negative affect on humans. However, mutation can also disrupt normal gene activity. Sometimes DNA mutations don’t give a good or bad affect, the gene might just be different.