Genetics What is Albinoism Albinoism is a recessively

Genetics

What is Albinoism? • Albinoism is a recessively inherited condition affecting about one in 17, 000 people. A person who inherits albinism usually inherits a recessive gene for the condition from each parent, though this is not the case in ocular albinism. The condition, though often fatal in other animals, has almost no impact on life expectancy or overall health in humans, but does affect vision to varying degrees.

Albino Characteristics • Little or no pigmentation in the eyes, skin, and hair (or in some cases in the eyes alone). • The altered gene does not allow the body to make the usual amounts of a pigment called "melanin". • True albinos have pink eyes and very light skin and hair.

These are not albinos; they have pigmented eyes.

White Bengal Tiger

White Bluebonnets

Pink Bluebonnets

Mutations A change in genetic information • Can occur randomly (naturally) • Or can be deliberately caused in the laboratory by scientists • Inherited • Not always harmful http: //www. accessexcellence. org/

Helpful Mutations -Some mutations are necessary for the survival of a species. -Mutations are the driving factor behind evolution -These are also known as adaptations Ex. Bacteria that are unaffected by antibacterial soap.

Sickle Cell Anemia • This genetic mutation first was discovered in Africa. – The red blood cells of individuals with this characteristic are the abnormally shaped. – This was an advantage because people with this mutation are immune to malaria which is one of the leading causes of death in Africa – People with Sickle cells lived longer on average because of their immunity to malaria which made them produce more children with the trait.

Camouflage • Some species are born with specific color patterns which make them more likely to survive then others of the same species. Longer life spans often lead to a greater chance of your genetic material being passed on to offspring because more children are born.

Camouflage Images

Camouflage images continued

Mimicry • This is an individual of a species acts like another object, usually to hide from predators or to ambush prey. • This increases the survival chances of an individual.

More Mimicry

Evolution is the change in the inherited traits of a population of organisms through successive generations. When a population splits into smaller groups, these groups cangiven sufficient time and enough environmental differentation—evolve independently and diversify into new species

Key Points • Charles Darwin’s main points on evolution – Species change over time – All organisms share common ancestors with all the other organisms that exist – Evolution takes a long time to happen, over many successive generations • Today scientist have seen this happen much more quickly

Natural Selection 4 components of natural selection • Variation-organisms exhibit differences within a species • Some traits are consistently passed on • Each generation experiences high mortality due to a struggle for resources • Individuals possessing traits for being well suited to survive will do so and have a greater chance for passing on their traits to many offspring

Summary of ideas • From one generation to the next, the struggle for resources (what Darwin called the “struggle for existence”) will favor individuals with some variations over others and thereby change the frequency of traits within the population. This process is natural selection. The traits that confer an advantage to those individuals who leave more offspring are called adaptations. Examples Evolution and Natural Selection

HUMAN INTERVENTION

Selective breeding

Selective breeding- this is the process of breeding animals or plants to acquire a specific trait. A) This has been done to many species throughout history but none more prevalently then the Dog B) Our plethora of modern day dog breeds is believed to have originate from one specific type of dog. The Wolf.

Hybrid Plants and Animals A hybrid is a cross between two species of organisms that would normally not interact with each other in the wild

The Liger • The Liger is the result of breeding a female Tiger to a male Lion. • The liger has both stripes and spots. The stripes are inherited from its tiger parent and the spots from the lion parent. • On their hind legs, ligers stand approximately 12 feet tall. At most, ligers may weigh up to 1, 000 pounds.

The Cama is the result of breeding a Llama to a Camel. Parents in background of picture.

The Zebroid is the result of breeding a female Horse and a male Zebra. The Zedonk / Zonkey is the result of breeding a female Donkey and male Zebra.

Geep - These are the result of a sheep and a goat.

The Mule is the result of breeding a female horse (mare) to a male donkey (jack). The mule is superior to the horse in strength, endurance, intelligence and disease resistance.

Maroon & Red Bluebonnets

Strange New Hybrids Zant

Two Clobster

Squiger

African Retriever

African Terrier

Caowl

Bat Frog

Gorrelephant

California Condor

Cloning Futhi

What is Cloning? • Duplicating a person e. g. identical twins. This is called “Reproductive” cloning. • Duplicating part of a person e. g. a heart or liver, or even just a few cells. This is called “Therapeutic” cloning.

What does this mean? Usually we get half our genetic information from each of our parents: 50% + 50% = 100%

In Cloning… • 100% of genetic information comes from one individual. E. g.

Could Make

Is a clone genetically identical? Almost – but not quite. Even identical twins are different due to the slight differences in the environment that they experience. Clones would be even more different as they would live in a very different environment and time as a form of “delayed identical twin”.

Therapeutic Cloning • Made in the same way as reproductive cloning except the embryo is not implanted; • Stem cells are harvested from the embryos which kills it; • The stem cells are used to grow different types of cells;

Hot Debate Stem Cell Research Embryonic V. S. Adult Reactions: The Cloning Debate When do you believe life begins?

Is Cloning Allowed? Different countries have different laws for the different types of cloning. Some countries (led by USA) want a global ban on all types of cloning, while others want a ban on certain types. In South Africa there are currently no laws against cloning.

Questions to Ponder • Do you think cloning is ethical for humans? • If you had a clone would it be your child or your delayed twin? • Does a clone have a soul? • What about all the duds? • What about creating clones for organs? • Who should decide who is cloned?

More Questions Ethical questions cont… • Who should have access to cloning technology – only people with good genes? • Who should pay for the cloning? • Should we be able to use this technology to design our children? (Gattaca) • Who does genetic information belong to? • Should people with genetic diseases be cured? Should they have children?

GENETIC ENGINEERING The selective, deliberate change of genes (genetic material) by man. The technique of removing, modifying or adding genes to a DNA molecule in order to change the information it contains.

What is a transgenic? • Concept Based on the Term Transgene – the genetically engineered gene added to a species Ex. – modified EPSP synthase gene (encodes a protein that functions even when plant is treated with Roundup) Transgenic – an organism containing a transgene introduced by technological (not breeding) methods Ex. – Roundup Ready Crops

Why are Transgenics important? • We can develop organisms that express a “novel” trait normally found in the species • Extended shelf-life tomato (Flavr-Savr Herbicide resistant soybean (Roundup Ready

Bright face of genetically modified corn plant: pestinfected non-GM (left) and pest-free GM plant (right) planted side-by-side in a field trial. (photo: Dr. Yu Jialin, China Agricultural University)

Agriculture Transgenics On the Market Insect resistant cotton – Bt toxin kills the cotton boll worm • transgene = Bt protein Virus resistance - papya resistant to papaya ringspot virus • transgene = virus coat protein

French genetic researchers created Alba for artist Eduardo Kac. Thanks to genes borrowed from a jellyfish, the albino rabbit glows green when placed under special lighting. In regular light, Alba appears like any other furry white rabbit. But place her under a black light, and her eyes, whiskers and fur glow a otherworldly green.

"Glow in the dark" fish. these genetically modified fish were developed by a Taiwanese aquatic firm, Taikong Group. They are planning to reproduce these fish in numbers and sell them for pets.

http: //www. fluorescentpets. com/index. htm

Scientists in the agriculture department of the Hebrew University in Rehovot have genetically engineered a chicken that has no feathers.

Some Ag Biotech Products Are Discontinued, Why? Poor Quality • Flavor Saver tomatoes (Calgene) Negative Consumer Response • Tomato paste (Zeneca) Negative Corporate Response • New Leaf (Monsanto) Universal Negative Publicity • Star Link corn (Aventis)