By Nick Mante

BASIC PRINCIPLES OF GENETICS

All living things look and act the way they do because of the traits they inherited from their parents. Traits are passed along from generation to generation by genes through the process of reproduction. All offspring receive half of their genes from their mother and the other half from their father. You receive one allele, one member of a pair of genes in a specific spot on a chromosome that controls the same trait, from each parent for each trait that you have.

Traits are controlled by dominant and recessive allelles. A dominant allele always shows up when it is present and hides the recessive alleles. A recessive allelle only shows up when the dominant one is not there. An organism will normally be either homozygous or heterozygous and if you’re heterozygous then the dominant allele will mask the recessive allele.

When alleles are co-dominant both of the alleles show in the organisms appearance. Neither allele is dominant or recessive so neither is hidden in the offspring.

THE ALLELES OF TWO PARENTS COMBINE TO EXPRESS TRAITS IN

OFFSPRING. For example, every person has two genes for eye color. When a person has two identical

genes, he will have eyes of that color. Another person may two different genes, and he will

have eyes the color of the dominant gene. With eye color, the gene for brown eyes is

dominant (B). The gene for Blue eyes is recessive (b). If a person has one B gene and one b

gene or two B genes, then that person will have brown eyes. If a person has bb eye genes,

then the person will have blue eyes.

Parents with Brown Eyes and Recessive Genes

In this diagram, both the mother and father have brown eyes, but they both have the

recessive gene for blue eyes as part of their genetic makeup. There is a 1 in 4 or 25% chance

that their child will have blue eyes.

#1

One Brown Eyed Parent with Recessive Gene

In this diagram, the mother has brown eyes with the recessive blue eye gene

and the father has blue eyes. There is a 1 in 2 or 50% chance that their child will

have blue eyes.

#2

Brown Eyed Parent without Recessive Gene

In this diagram, the father has blue eyes and the mother has brown eyes without the

recessive gene. In all of the possible combinations for the children, there is one of the

dominant B genes. All of the children will have brown eyes.

The results would be the same in diagram 2 if the Mother had blue eyes and the Father had

Brown eyes with a recessive blue gene, or in diagram 3 if the Father had the brown eyes

and the Mother had blue eyes.

#3

The Human Genome Project (HGP) formally began in October 1990 and was completed in 2003.

It was an International Effort. The Human Genome Project (HGP) is a research program

formed to complete the mapping and understanding of all the genes of human beings. All our genes together are known as our "genome." It explores our genetic environment to help us understand and improve our lives.

Its primary goal is a listing and location of our genes — the single unit of heredity responsible for how we develop from conception, how we grow and mature, how we live, and how we die.

Major goals were to identify all the estimated 20,000-25,000 human genes on the 46 chromosomes, find the sequences of all the base pairs in human DNA, store the information in a data base for further study, develop tools for analyzing data, and address the ethical, legal, and social issues that would come from the project.

Sequencing the human genome involved laying out the entire genetic code in human DNA.

The hereditary material is the double helix of deoxyribonucleic acid (DNA), which contains all human genes. DNA is made up of four chemical bases, pairs of which form the "rungs" of the twisted, ladder-shaped DNA molecules. All genes are made up of stretches of these four bases, arranged in different ways and in different lengths.

During the HGP, researchers deciphered the human genome in three major ways: determining the order, or "sequence," of all the bases in our genome's DNA; different sequences make up different genes, making maps that show the locations of genes for major sections of all our chromosomes; and producing linkage maps through which inherited traits (such as those for genetic disease) can be tracked over generations.

The step after sequencing is decoding, figuring out what the sequence of letters means. After that, scientists must determine which part of the sequence fits on which human gene and what each gene does. These last steps may take decades to complete.

The HGP revealed that there are probably 25,000 human genes. The completed human sequence can now identify their locations. The result of the HGP has given the world a resource of detailed information about the structure, organization, and function of the complete set of human genes. This information can be thought of as the basic set of inheritable "instructions" for the development and function of a human being.

HOPE

The hope is that this work will help in thedevelopment of drugs that work at the genetic level, orthat it may allow for the actual replacement ofdefective genes with normal ones. Some headway hasalready been made in the areas of skin cancer,diabetes, Alzheimer's disease, migraines, andnarcolepsy.

ETHICS - Some people think it’s unethical because it’s just not right to mess with nature. A person’s DNA is confidential. They also want to avoid stigmatizing individuals who carry certain genes.

LEGAL - There are many legal issues. For example privacy and confidentiality of genetic information. Should be have to tell people about our genes? We have to worry about fairness in the use of genetic information by insurers, employers, courts, schools, adoption agencies, and the military, among others. There is also some fear that insurance companies will deny coverage for "preexisting" conditions to people carrying a gene that predisposes them to particular diseases, or that employers might start demanding genetic testing of job applicants.

Who should have access to personal genetic information, and how will it be used?

SOCIAL - Socially it can change a lot of things. Human responsibility, free will vs genetic determinism, and concepts of health and disease.

Do people's genes make them behave in a particular way?Can people always control their behavior?What is considered acceptable diversity?Where is the line between medical treatment and enhancement?

Since the HGP started, knowledge of human genetics has grown, leading scientists and doctors to develop and provide genetic tests for over 1500 conditions currently. It has helped to identify diseases in individuals as well as to assist doctors decide the best form of treatment. However, the medical developments occurred in advance of policies to ensure protection of individual rights. In the mid-1990’s, some members of Congress became concerned about how some entities might use an individual’s genetic information without laws designed to protect an individual from discrimination based on the individual’s genetic information. Beginning in 1995, members of the House of Representatives and the Senate began to develop legislation that would severely limit how employers and insurers could obtain and use genetic information. The effort to protect individuals from discrimination based on their genetic information ended this year with the passage of the Genetic Information Nondiscrimination Act of 2008 (GINA), a bipartisan effort designed to prevent insurers from underwriting and employers from making employment decisions based on genetic information. Heralded by Senator Kennedy as “the first civil rights bill of the new century of the life sciences”, the statute makes significant strides towards protecting individuals from discrimination based on their genetic information.

Prohibits group and individual health insurers from using a person's genetic information in determining eligibility or premiums

Prohibits an insurer from requesting or requiring that a person undergo a genetic test

Prohibits employers from using a person's genetic information in making employment decisions such as hiring, firing, job assignments, or any other terms of employment

Prohibits employers from requesting, requiring, or purchasing genetic information about persons or their family members

Will be enforced by the Department of Health and Human Services, the Department of Labor, and the Department of Treasury, along with the Equal Opportunity Employment Commission; remedies for violations include corrective action and monetary penalties

A genetic disorder is an illness caused by abnormalities in genes or chromosomes. While some diseases, such as cancer, can be caused partly by genetic disorders, they can also be caused by environmental factors. The disorders may be influenced by several factors. When a disease runs in a family, faulty genes are passed from parent to child. Or a change in the genetic material, a mutation, may occur during formation of an egg or sperm cell. Mutations may also appear during fetal development. Disorders occur where there is a problem with an individual's DNA.

SINGLE GENE DISORDERS A single gene disorder is the result of a single mutated gene. They can be traced through

families and their occurrence in later generations can be predicted. The defective version of the gene responsible for the disease is known as a mutant allele or a disease allele.

Single gene disorders can be divided into a number of different categories according to how they are transmitted from generation to generation. Some are described as dominant diseases because only one mutant allele is required, and such diseases tend to crop up in every generation.

Other diseases are described as recessive because both copies of the gene must be defective in order for the disease to occur. These recessive diseases often skip generations because mutant alleles can be carried without any effect if a normal allele is also present.

Many single gene disorders affect both sexes equally. However, where the relevant gene is present on the X-chromosome, the associated disease tends to be more common in males.

Examples - sickle cell anemia and cystic fibrosis

Chromosome abnormalities are errors on any of the body's 23 pairs of chromosomes, such as broken or missing pieces or too many pieces or copies. An error (or mutation) in a person's genes. Genes are carried on chromosomes, structures within the cell that carry information about all of a person's inherited traits. A person's genes may be damaged prior to, or during, conception and abnormal genes may be passed down through a family.

Each person should have 46 chromosomes, arranged into 23 pairs. One pair of chromosomes, the sex chromosomes, are labeled XX for female and XY for male. The restof the chromosome pairs are numbered 1-22. This normal set of 23 pairs of chromosomes is called the diploid number of chromosomes. An individual pair of chromosomes is called a disomy. In the normal situation one chromosome from each pair is inherited from

the mother and the other from the father. However, abnormalities can occur in which a whole chromosome or a portion of a chromosome can be added or deleted. This occurrence results in addition or subtraction of genes, which cause can cause significant problems with growth and development..

The image below shows a G-banded normal male karyotype, a picture of a person’s chromosomes, which is a figure where the chromosomes are paired together and lined up in order from 1-22, X and Y.

Down syndrome, shown in the karyotype image below, occurs when a person has 3 copies of chromosome 21 instead of the usual 2 copies.

Multifactorial disorders are conditions caused by many contributing factors. They can be caused by the interaction of genetic and sometimes also non-genetic, environmental factors. Common medical problems such as heart disease, diabetes, and obesity do not have a single genetic cause—they are likely associated with the effects of multiple genes in combination with lifestyle and environmental factors.

Multifactorial inheritance refers to the pattern of inheritance of common health problems and rarer conditions caused by a combination of both genetic and other factors that may include internal factors such as ageing and exposure to external environmental factors such as diet, lifestyle, and exposure to chemicals or other toxins.

• Multifactorial conditions don’t always develop even if there is a faulty gene(s)

• The inherited faulty gene(s) increases the risk that a person may develop a condition but unless other factors are present, the condition may never develop at all. In other cases, the exposure to particular environmental factors (or even simply ageing) interacts with an inherited predisposition due to faulty gene and the development of th econdition is ‘triggered’.

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Genetic counseling helps perspective parents with a genetic disorder by determining if family members are at risk for a particular conditions by examining their family health history. Family history is very important. They explain the chances that their disorder can be passed to a child and what can possibly happen. They can also do early detection tests and preventative strategies in which the triggering factors, if known, are avoided.

Karyotypes can predict genetic disorders by showing the details of a families chromosomes. When doctors study a human karyotype they look for some certain features. They check to see if the 46 chromosomes are present. They check for the presence of the two identical chromosomes and 2 sex chromosomes and they check if there are any missing or rearranged chromosomes.

What is Cloning ?? What is Cloning ??

Cloning is the creation of an organism that

is an exact genetic copy of another. This

means that every single bit of DNA is the

same between the two!

Cloning an animal, or any other organism, means

making an exact genetic copy of that organism

HOW do they Clone? Cloning means the creation of a life. But creating human life through cloning is where the

cloning debate becomes controversial in many categories. That created life has the exact DNA structure of the host from which the DNA was extracted.

To clone an animal, first a donor cell is found, which has its original DNA taken out and discarded. Next is the addition of a nucleus from the desired animal that is to be cloned. The third step involves implanting the combined cell into the animal that the donor cell was taken from.

Cloning animals has been around for awhile now and the 1st successful one was Dolly the sheep. To create Dolly scientists used Somatic Cell Nuclear Transfer (SCNT). A somatic cell is a cell from any part of the body other than the reproductive cells. The nucleus is the portion of each cell that contains the DNA that makes each life form unique. The nucleus of the somatic cell is transferred to a donor egg cell, which had its nucleus removed.

With Dolly, a somatic cell from an adult female sheep was isolated. The SCNT method was used and an embryo developing was implanted into a surrogate female sheep, which was carried to term resulting in Dolly. And though Dolly's case was a great achievement, Dolly died soon after her birth. Scientists are not able to clone humans like livestock, yet.

Since 1997, gradual improvements in cloning technology have enabled researchers to generate mouse, cattle, goat, pig, deer, rabbit, cat, mule, and horse clones.

What about cloning extinct and Endangered Animals?

In January 2009, for the first time, an extinct animal, the Pyrenean ibex was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved DNA of the skin samples from 2001 and domestic goat egg-cells. (The ibex died shortly after birth due to physical defects in its lungs.)

Why should we clone endangered and extinct animals?

I am for cloning endangered and extinct animals.ARGUMENTS -To protect endangered species from going extinct, manyspecies are hard to breed and attempts have beenunsuccessful so they can’t keep up with the extinctionrate.Keep living things in nature as they have always been.It offers a possible route to saving the unique geneticmake-up of a species in the body of a living creatureThe cloned offspring could be used for captive breedingto boost wild populationsIt does no harm to wild populations in another speciescan be used as surrogate mothers

CLONING ANIMALS>>> MORALLY RIGHT???WHAT DO OTHER PEOPLE THINK? Some were asked….Regardless of whether or not you think it should be legal, for each one, tell whether you personally believe that in general it is morally acceptable or morally wrong.) How about...cloning animals?

Gallup Poll, [May, 2010]

LIKELYHOOD OF CLONING EXTINCT ANIMALS –In the next 40 years, how likely do you think it is that...scientists will bring back an extinct animal species by cloning it...do you think this will definitely happen, will probably happen, will probably not happen, or will definitely not happen?

Note: Asked of Form 2 half sample Pew Research Center for the People & the Press Political and Future Survey, [Apr, 2010]

Gene – a segment of DNA on a chromosome that codes for a specific traitChromosome- A doubled rod of condensed chromatin; contains DNA that carries genetic information Cloning - a cell, cell product, or organism that is genetically identical to the unit or individual from which it was derived. DNA- Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspringEngineering - The application of science to practical uses such as the design of structures, machines, and systems. Genetic Engineering - The science of altering and cloning genes to produce a new trait in an organism or to make a biological substance, such as a protein or hormone. Genetic engineering mainly involves the creation of recombinant DNA, which is then inserted into the genetic material of a cell or virus.

Heredity - the passing of traits from parents to offspringMutation – a change in a gene or chromosome

Cable News Network, USA Today. CNN/USA Today/Gallup Poll # 2000-20: Microsoft/Parents/'Socially Responsible' [computer file]. 1st Roper Center for Public Opinion Research version. Lincoln, NE: Gallup Organization [producer], 2000. Storrs, CT: The Roper Center, University of Connecticut [distributor], 2001.

http://www.sciencekidsathome.com/science_topics/genetics-a.htmlCopyright © 2011 Science Kids at Home, all rights reserved

http://learn.genetics.utah.edu/content/tech/cloning/whatiscloning/"Genetic Science Learning Center, University of Utah, http://learn.genetics.utah.edu." No specific request for permission is needed for this purpose.

https://www.chp.edu/CHP/P02124©Children's Hospital of Pittsburgh Feb. 3, 2008

WORK CITED

Human Genome Project - Ethical Issues - Job, Social, Genetic, Dna, Scientific, Genes, Press, Special, and Sciencehttp://medicine.jrank.org/pages/2413/Human-Genome-Project-Ethical-Issues.html#ixzz1HYeK7rPi

<http://dir.yahoo.com/Health/Diseases_and_Conditions/Genetic_Disorders/>.www.encyclopedia.com/doc/1G2-3408600133.htmlJournal of Diversity Management – Fourth Quarter 2008 Volume 3, Number 4 33 .The Genetic Information Nondiscrimination Act of 2008 .Carrie G. Donald, University of Louisville, USA ,Adam K. Sanders, University of Louisville, USA http://www.cluteinstitute-onlinejournals.com/PDFs/1713.pdf

http://en.wikipedia.org/wiki/Cloning#Cloning_extinct_and_endangered_species

The New England Journal of Medicinehttp://www.nejm.org/doi/full/10.1056/NEJMp0803964Kathy L. Hudson, Ph.D., M.K. Holohan, J.D., and Francis S. Collins, M.D., Ph.D. N Engl J Med 2008; 358:2661-2663June 19, 2008

http://www.actionbioscience.org/genomic/carroll_ciaffa.htmlActionBioscience.org is a resource of the American Institute of Biological Sciences.

"Human Genome Project" Compton's by Britannica. Britannica Online for Kids.Encyclopædia Britannica, 2011. Web. 24 Mar. 2011.<http://kids.britannica.com/comptons/article-9326823/Human-Genome-Project>. APA style:Human Genome Project ( 2011). In Compton's by Britannica. Retrieved from http://kids.britannica.com/comptons/article-9326823/Human-Genome-Project

http://ghr.nlm.nih.gov/handbook/mutationsanddisorders?show=all#complexdisorders, Genetics Home Reference, March 20, 2011