DNA technology

Why DNA Technologies

• Goal was to determine the entire genome sequence and use it to differentiate between individuals as well as to identify the presence of genes involved in causing disease

• Ability to recombine DAN to create new possibilities in genetically modified plants and animals

• Gene therapies, genetic testing and cloning methods were also developed

Human Chromosomes/Genomes

The structures within cells that contain the genetic information of an individual. Humans have 23 pairs of chromosomes, totaling 46.

RFLP (Restriction Fragment Length Polymorphism)

It is RFLP is a technique to detect variation in DNA sequences among individuals. It relies on the fact that DNA sequences differ among individuals leading to differences in the length of DNA fragments produced when DNA is cut with restriction enzymes. It is used in DNA fingerprinting

Polymerase Chain Reaction (PCR)

It is a laboratory technique for rapidly producing mullions to billions of copies of a specific segment of DNA which then can be studied in greater detail. It involves using short synthetic DNA fragments called primers to select a segment of the genome to be amplified and then multiple rounds of DNA synthesis to amplify that segment. Once the reaction is complete the sample is subjected to electrophoresis. It allows very small samples of DNA to be increase for analysis

Recombinant DNA Technologies

The process of combining DNA from different organisms to express genes from one organism to another allows for genetic engineering. It is possible because the genetic code is universal. it allows for bacterial genes to be expressed in plants, and fish genes in animal and ent genes in animals.

Genetic Testing

The analysis of an individual's DNA to identify the presence of genes associated with specific traits or diseases such as cancer, diabetes, or Alzheimer's. It is used in fetuses to test for Down’s syndrome and other chromosome abnormalities. It is not a predictor of intelligence or other attributes not related to specific traits or diseases. Testing must be followed by genetic counseling as well as a consideration of ethical, moral, and religious issues before a decision is made to take action against the result

Prenatal Genetic Testing

Genetic testing is performed during pregnancy to screen for or diagnose genetic disorders in the fetus. For screening you can use maternal blood serum, ultrasound and non-invasive prenatal testing. For diagnosing use chorionic villus sampling and amniocentesis.

Gene Therapy

A technique that involves replacing a nonfunctional gene with a functional one to treat genetic diseases. The new version of a gene is introduced into human cells using a virus vector and must be expressed in the cell and the modified cell replicates. Has not been a very successful technique.

Personalized Medicine

The use of medical approaches tailored to an individual's genetic profile to provide more effective and personalized treatments.

Cloning of Animals

The production of genetically identical copies of an individual animal using somatic cells. It was used to create Dolly the sheep. The result is a genetically identical copy of the parent from which the somatic cell was derived.

Implications of DNA Technology

The ethical, moral, societal, and religious considerations that need to be taken into account when using DNA technologies. The ability to alter DNA should be considered cautiously. There is a risk of genetic discrimination occurring where individuals who ar known carriers of disease-causing genes may be denied opportunities.

Restrictions on Use of DNA Technology

The limitations and regulations placed on the use of DNA technologies, such as restrictions like no human cloning or genetic engineering. Research on human cells/stem cells need special permits, research on recombinant DNA requires special permits and many ethical and scientific regulation on conducting research involving human subjecst

Why is it useful to obtain information like the genome project

Helps to personalize medicine for efficacy, study protein function and help to understand genetics for medical purposes

Process of RFLP

DNA is extracted from blood, saliva, skin cells etc. The DNA is digested and cut using a restriction enzyme DDE!. The enzyme recognizes specific sites on the DNA molecule to cut (DNA fragmentation). The restriction fragments produce during fragmentation are then analyzed using gel electrophoresis. The fragments are negatively charged and are easily separated by electrophoresis which separates molecules based on size and charge. Fragments migrate towards the positive electrodes and smaller fragments move faster through the gel leaving the larger ones behind. Thus DNA samplers are separated into distinct bands on the gel. The gel is treated with luminescent dyes in order to make the DNA bands visible

Uses of RFLP

Solving crime by identify the same bands on the suspect and the criminal / paternity cases

Why is PCR useful

because it can produced billions of a specific DNA fragment of gene from just a small sampled of DNA. It is useful in crime scenes to identify suspected individuals

Steps of PCR

Denaturation - splits the target sequence in half

Annealing - Primers are added to both strands

Extension - New nucleotides are added

Example of genetic engineering

1. Creating Insulin from bacteria. Genes of interest were cloned and expressed to produce human growth hormone, insulin and other proteins

2. In plants, GMOs were produced. Creating a plant that’s resistant to cold and pesticides. They took DNA from fish that survive in cold environments and put it into plants

3. In monkeys, a jellyfish gene was introduced

How to recombine DNA in a bacterium

Insert a gene of interest into a plasmid (small circular DNA molecule in bacteria), insert said plasmid into a bacterial cell. The host cell then grows and replicates into multiple cells with the gene of interest.

How Genetic Engineering is performed

A restrictive enzyme cuts sugar phosphate backbones, DNA fragment added from another molecule is cut, base pairing occurs and DNA ligase seals strands

Example of GM animals approved for use

Expression of growth hormones in salmon to make them grow faster

What can you do with genetic testing

• Diagnose disease

• Pinpoint genetic factors that caused disease

• Predict how severe disease might be

• Choose best medicine and dosage

• Discover genetic factors that increase your disease risk

• Find genetic factors that could be passed to children

• Screen newborns for certain treatable conditions

Diseases that could be cured by gene therapy

Cystic fibrosis and hemophilia,

Pros of Cloning Animals

Can be used to breed for a specific trait and create a superior animals by cloning it like a superfast horse or fast egg-laying hens

Cons of Cloning Animals

Cloned animals had features of the older parent’s the the nucleus of the cells were the nucleus of an adult instead of a child. They would develop arthritis and cell had shorter telomere. They would be have like an older 2 year old like an older person in a young body. A clone cat CC had a different personality from it’s mother even though they are genetically the same.