Basic principles of genetics A Dominant allele is controlled by its trait always shows up in the organism when the allele is present. A Recessive allele is controlled by when an allele is masked when a dominant allele is present. Traits are controlled with co -dominant alleles through the alleles are neither dominant nor recessive. As a result, neither allele is masked in the offspring. The alleles of 2 parents combine to express traits in off springs by using Punnett squares.
Human Genome Project It started in 1990. The main goal of the Human Genome project was to identify the DNA sequence of every gene in the human genome. On May 21st, President Bush signed into law the Genetic Information Nondiscrimination Act (GINA), which prohibits U.S. insurance companies and employers from discriminating on the basis of information derived from genetic tests. GINA passed both houses of Congress with a vote in the U.S. House of Representatives of 414 to 1. The bill had passed in the House twice before, most recently last year when the vote was 420 to 3. The U.S. Senate unanimously passed the current bill after compromises were reached on areas of disagreement that had held up its passage for several months. GINA protects Americans from discrimination based on information derived from genetic tests. It forbids insurance companies from discriminating through reduced coverage or pricing and prohibits employers from making adverse employment decisions based on a person’s genetic code. In addition, insurers and employers are not allowed under the law to request or demand a genetic test. Social- How does personal genetic information affect an individual and society's perceptions of that individual? How does genomic information affect members of minority communities? Who should have access to personal genetic information, and how will it be used? “Because of this legislation, Americans will be free to undergo genetic testing for diseases such as cancer, heart disease, diabetes, and Alzheimer’s without fearing for their job or health insurance. Who owns and controls genetic information? Legislators are beginning to address issues of genetic privacy. Medical records are not private. If you have ever applied for individual life, health, or disability insurance, information about you may be in the Medical Information Bureau (MIB), a computerized database of medical and some nonmedical information. Originally created to prevent consumer fraud, MIB holds information on 10 million to 20 million Americans. If an insurance applicant has a condition pertinent to health or longevity, such information must be provided by insurance companies to MIB. Nonmedical information that could affect insurability, such as an adverse driving record or participation in hazardous sports, also can be reported. You must give consent to MIB to establish your record or for an insurance company to search your MIB record. If you don't give consent, the insurance company may automatically deny coverage. Next time you fill out an insurance application, examine it carefully. I recently received a letter urging me to apply for mortgage insurance, and sure enough, if I signed the application, I was giving permission for the company to access my MIB file. An individual in one of our recent workshops informed the group that he was denied mortgage insurance because of diabetes, a condition listed in his MIB file. As this database grows, some people are concerned that corporations, agencies, and others will have access to our medical records and genetic information just as they do to our credit histories.
Genetic Disorder Single-gene (also called Mendelian or monogenic) - This type is caused by changes or mutations that occur in the DNA sequence of one gene. Genes code for proteins, the molecules that carry out most of the work, perform most life functions, and even make up the majority of cellular structures. When a gene is mutated so that its protein product can no longer carry out its normal function, a disorder can result. There are more than 6,000 known single-gene disorders, which occur in about 1 out of every 200 births. Some examples are cystic fibrosis, sickle cell anemia, Marfan syndrome, Huntington’s disease, and hereditary hemochromatosis. Single-gene disorders are inherited in recognizable patterns: autosomal dominant, autosomal recessive, and X-linked. Multifactorial (also called complex or polygenic) - This type is caused by a combination of environmental factors and mutations in multiple genes. For example, different genes that influence breast cancer susceptibility have been found on chromosomes 6, 11, 13, 14, 15, 17, and 22. Its more complicated nature makes it much more difficult to analyze than single-gene or chromosomal disorders. Some of the most common chronic disorders are multifactorial. Examples include heart disease, high blood pressure, Alzheimer’s disease, arthritis, diabetes, cancer, and obesity. Multifactorial inheritance also is associated with heritable traits such as fingerprint patterns, height, eye color, and skin color. Chromosomal - Chromosomes, distinct structures made up of DNA and protein, are located in the nucleus of each cell. Because chromosomes are carriers of genetic material, such abnormalities in chromosome structure as missing or extra copies or gross breaks and rejoinings (translocations) can result in disease. Some types of major chromosomal abnormalities can be detected by microscopic examination. Down syndrome or trisomy 21 is a common disorder that occurs when a person has three copies of chromosome 21. Compare- Contrast A single gene – mutation occurs in only the DNA of one sequence of gene. This is inherited with the multifactorial. The Multifactorial gene- mutation is in multiple genes. Its more difficult to analyze than single gene or chromosomal disorders. Most common is multifactorial disorders. Also, multifactorial inheritance is also associated with this. Chromosomal Gene- chromosome structures make –up DNA and protein, because chromosomes are carriers of genetic material abnormalities in chromosomes are missing or there4 are extras, thus, causing the abnormality. This can be seen by microscope and detected in the moms fetal blood. .Genetic counselors can help you to make informed, personalized decisions about your genetic health. As genetics professionals, they can help identify your potential genetic health risks, give you information about genetic conditions and inheritance patterns, discuss genetic testing options, help you understand your genetic results, and provide support throughout the process. People who are born with an abnormal number of chromosomes often have genetic disorders because their cells contain too much or too little genetic information. Scientists can predict genetic disorders by looking for extra or missing chromosomes in a karyotype .
<ul><li>Argument 1 Pros According to the National Institutes of Health , the main benefit of fetal stem cell research is that embryonic stem cells are pluripotent, which means they have the potential to become any type of cell that might be needed therapeutically. Adult stem cells are also flexible, but less so. Read more: Pros & Cons of Fetal Stem Cell Research | eHow.com http://www.ehow.com/facts_6371392_pros-fetal-stem-cell-research.html#ixzz1HAIj2iFa </li></ul>
One important tool that geneticists use to trace the inheritance of traits in humans is a pedigree.
Researchers had their first successes with genetic engineering when they inserted DNA from other organisms into bacteria.
Human cloning is an extraordinarily contentious issue. Cloning a human embryo involves taking a cell (or cells) from a pre-existing embryo and growing it into its own, separate embryo with identical DNA. The new embryo can develop either in vivo -- through implantation into a woman's uterus -- though there are laws against this in most countries, or in vitro (in, for example, a Petri dish). Cloning an embryo is like creating a twin, but through inducement, rather than a spontaneous, natural process. Read more: http://www.brighthub.com/science/genetics/articles/16669.aspx#ixzz1HAEMUymz
Argument 2 Cons The biggest drawback of fetal stem cell research is that for many people, especially conservative Christians, it seemingly presents an ethical dilemma, as cells must be harvested from a human embryo Read more: Pros & Cons of Fetal Stem Cell Research | eHow.com http://www.ehow.com/facts_6371392_pros-fetal-stem-cell-research.html#ixzz1HAJDwBTd
Argument 3 Pros Stem cells, as opposed to other cells, have the potential ability, once transplanted, to grow and transform into almost any kind of cell in any part of the body. The most obvious pro of stem cell research is in the area of medical disease. Current research is helping to understand most of the serious diseases, from Alzheimer’s, Parkinson’s and strokes to diabetes, heart disease, bone diseases, spinal cord injuries and cancer. Injured or destroyed cells can be replaced by new and healthy stem cells that will adapt to the area and type of cell for any injury or disease. Other benefits of stem cell research are in the area of damaged organs and transplants, where these cells can be used to reduce risks in transplants or repair damaged areas. Another area is the possibility of cloning and regeneration, which can mean the ability of stem cells to replicate cells in vital organs. These are all pros in connection with the actual use and results of research.
Argument 4 Cons The cons in the use of stem cell research come from opponents who say that stem cell research is unethical or immoral. They maintain that cloning puts people in the position of tampering with human life or acting like God . Regardless of the fact that some significant benefits can accrue from stem cell research, opponents believe it all may ultimately lead to the ability to clone human beings, which they argue is immoral, unethical and disastrous for mankind.
There are also pros and cons in harvesting stem cells for the research and the methods used. Pros and cons differ somewhat depending on where the stem cells are being taken from. The three key areas are adult cells, which can be taken from bone marrow or the peripheral system, umbilical cord cells and embryonic cells. The pro of taking stem cells from bone marrow is that the cells are plentiful there. The con is that painful damage to the bone occurs when extracting stem cells there. Cells taken from the peripheral system do not cause damage when being extracted but take longer to extract. The pros of adult stem cells as opposed to the umbilical and embryonic ones are that they are taken from an adult patient’s own body, and the body does not reject them because there is a perfect DNA match. Umbilical cord stem cells are also plentiful, may be extracted during pregnancy and stored for future use for the baby or the parents and siblings. Pros and Cons of Harvesting Stem Cells
Conclusion Harvesting Stem Cells is good for medical disease and current research is helping to understand most of the serious diseases, from Alzheimer’s, Parkinson’s and strokes to diabetes, heart disease, bone diseases, spinal cord injuries and cancer. Injured or destroyed cells can be replaced by new and healthy stem cells that will adapt to the area and type of cell for any injury or disease.. Other benefits of stem cell research are in the area of damaged organs and transplants, where these cells can be used to reduce risks in transplants or repair damaged areas. I hope as geneticists continue with their research they will continue to find more pros.