Modern Genetics

Human inheritance Some traits are formed from single genes

(2 alleles) Some are formed from multiple genes

(multiple alleles) Example: blood type

Blood typesTypes: A, B, AB, O3 alleles control the blood type

A & B are co dominantO is recessive

SexChromosomesCarry genes that determine if a person is male or female

Each parent offers 2 alleles

Male X, YFemale X, X

Alleles on the X and Y chromosome are not the same

Sex Linked Genes Genes carried on the sex chromosomes A female has 2 X chromosomes: if one x

has a dominant gene and the other has a recessive, the dominant trait will show

In a male, there isn't corresponding alleles. If the X chromosome has a recessive trait, and there is no corresponding allele on the Y chromosome, then the recessive trait will show.

Therefore, males have a higher tendency to show recessive sex linked traits.

Carriers A heterozygous person Because they have the dominant allele, the

recessive trait doesn't show, but they can still pass it along to offspring

Genetic DisordersDef: an abnormal condition inherited

through chromosomes

Some are caused by mutationsSome caused by an change in

chromosome numberCystic fibrosisSickle cellHemophiliaDown syndrome

Pedigree Chart that tracks which family members

have a certain trait

Managing Disorders Karyotype: picture of the chromosomes in

a cell--can determine if a mutation or extra chromosome is present

Genetic counseling: to help coping with disorders

Therapy: to assist with disorders

Modern GeneticsSelective Breeding: is the process of selecting and breeding parent organisms to pass on particular traits to the offspring.

Examples:Horses, pigs, corn, dogsQuestion:What do you thing the animal to the left is? It has been selectively bred.

Modern GeneticsCross Breeding: A cross between two pure breed parents creating a hybrid.

Killer Bees: a cross between Brazilian bees with African bees to create a bee that would produce more honey.

Modern GeneticsGenetic Engineering: is the process in which a sequence of DNA from an organism is first isolated, then inserted into the DNA of another organism, changing that organism’s DNA.

Example:Taking genes from microorganism and inserting them into plants to produce a natural insect killing chemical.Inserting a bioluminescent gene into bacteria to make it glow.

Modern GeneticsGenetic Engineering vs. Organic

Most of you have eaten genetic engineered/ modified foods. Many plants have bacterial genes that make them more resistant to insects.

How many of you have eaten fruits without seeds?Picture:Here is a tobacco plant that glows.

Modern GeneticsCloning: is a technique that uses technology to make copies. It can be applied to a segment of DNA or the whole organism.

Examples:Bacteria: create human insulin which is used to help people with diabetes.A sheep named Dolly. (Nucleus Transfer)

Modern GeneticsCloning a Gene

Modern Genetics

Genome: is all the genetic material in an organism.

Modern GeneticsSo why clone?

1. Medicine2. Reviving endangered or extinct animals:

Jurassic Park!3. Reproducing a deceased pet4. Cloning humans

Modern GeneticsDNA Identification: The use of DNA to identify a person.

DNA Fingerprinting: Chart representing repeating base pairs

Example:Used in crime solvingA fun case at NOVA.DNA Evidence Video

Modern GeneticsWhat are Some Issues to Cloning?

The Good vs. Bad

What are the ethical issues?

Modern GeneticsThere are genetically engineered salmon that grow faster. They are breed in captivity, near rivers and stream. What might happen if they escape?

Modern GeneticsShould we label genetically modified foods?

Many companies already label food and products that have been genetically altered.