Unit 10 - Biotechnology

What are the three approaches can be used to treat adenosine deaminase (ADA) deficiency that leads to SCID?

1. A bone marrow transplant from a compatible donor 2. Purified ADA coupled to polyethylene glycol (PEG) 3. Gene therapy

Describe the experiment that was conducted using gene therapy to treat ADA deficiency.

1.Remove ADA-deficient lymphocytes from the patient with severe combined immunodeficiency disease (SCID). 2. Culture the cells in a laboratory. 3.Transfect the cells with a retrovirus that contains the normal ADA gene. Retroviruses insert their DNA into the host cell chromosome as part of their reproductive cycle. 4.Infuse the ADA-gene-corrected lymphocytes back into the SCID patient.

A researcher wishes to control the expression of a gene in a transgenic animal so that the gene is only expressed in a specific tissue. What kind of promoted would be best suited for their use?

A promoter from a protein that is only expressed in that tissue.

_____________ integrates into a specific site of human chromosome 19 (many people carry this harmless virus). A disadvantage is that it has a low titer.

Adeno-associated virus (AAV)

_____________ effects lung cell receptor epithelial cells. Nasal spray can be used to treat this.

Adenovirus

The inclusion of a methionine residue between insulin and the beta-galactosidase protein was to _____________.

Allow for the easy separation of the two peptides

The use of living organisms or the materials they produce in the development of goods or processes that are beneficial to humans is called _____________.

Biotechnology

______________ is broadly defined as technologies that involve the use of living organisms, or their products, to benefit humans.

Biotechnology

What is the purpose of the cyanogen bromide (CNBr) in the manufacture of insulin by recombinant bacteria?

Cleaves the protein from the beta-galactosidase protein

Gene knockins are used to study the effects of ______.

Consistent gene expression

What is the protocol for the successful cloning in sheep?

Donor sheep's mammary cell is extracted and grown in a tissue culture flask. Another sheep's unfertilized egg is extracted, and the nucleus is removed. The cells are fused together with electrical pulses. The donor nucleus from the mammary cell and the proteins from the enucleated egg initiate development of the egg into an embryo. The embryo is transferred into a surrogate ewe. Pregnancy proceeds and a sheep genetically identical to the donor sheep is born.

Use of animals to produce human proteins is an example of __________.

Gene addition

_____________ is when a cloned gene is inserted by non-homologous recombination, resulting in an additional copy of the gene in the genome.

Gene addition

In mice, researchers can produce a ______________, in which a gene of interest has been inserted into a particular site in the mouse genome.

Gene knockin

____________ is when a non-functional cloned gene is used to replace a normal gene by homologous recombination.

Gene knockout

_____________ is when a cloned gene is exchanged for the normal gene by homologous recombination.

Gene replacement

___________ is the introduction of cloned genes into living cells in an attempt to cure disease.

Gene therapy

What is an example of pharming?

Goats that produce human hormones in their milk

Gene knockout allows researchers to study ____________.

How the loss of normal gene function affects an organism

What was the hypothesis in using gene therapy to treat ADA deficiency?

Infecting lymphocytes with a retrovirus containing the normal ADA gene will correct the inherited deficiency of the mutant ADA gene in patients with ADA deficiency.

The first hormone made by recombinant DNA was ___________.

Insulin

What are some examples of medicines made from recombinant organisms?

Insulin, TPA, superoxide dismutase, factor VII, renin inhibitor, and erythropoietin.

Although there are many different genes that can contribute to cancer development there are two basic types of genes that are involved in deregulation of the cell cycle, which is a major hallmark of cancer. Oncogenes are genes that act in a dominant manner and experience a gain of function mutation to enhance cell's ability to divide. Tumor suppressors genes in general are recessive and mutations in tumor suppressor genes act as loss of function mutations to enhance a cell's ability to divide. Researchers have developed mouse models to study both types of genes. Of the list below which technique would be best suited for developing a mouse model for studying a tumor suppressor gene?

Knockout

In the treatment of ADA deficiency and SCID, which cell type was targeted for gene therapy?

Lymphocytes

Ian wilmit and his colleagues produced the first _____________ somatic clone, a sheep named Dolly.

Mammalian

An advantage of the ______________ approach is that it doesn't produce an elicit immune response.

Nonviral

In the _______________ approach, DNA protected by liposome is taken up by cell through endocytosis. DNA goes into nucleus and is integrated into genome. It is used by retroviruses and includes ectopic integration.

Nonviral

Gene therapy may involve the introduction of cloned genes into human cells by two methods: ____________ and _____________ approach.

Nonviral and viral

During somatic cloning, the ___________ from a somatic cell is inserted into an egg without a nucleus.

Nucleus

The production of medically important proteins in the mammary glands of livestock is called molecular _____________.

Pharming

________ can easily be cloned from somatic cells.

Plants

________________ produces two or more genetically identical individuals.

Reproductive cloning

The first human diseases that was successfully treated using gene therapy was ________.

Severe combined immunodeficiency diseases

How does gene addition (knock-in) work?

The gene of interest is cloned and flanked with pieces of DNA that are nonhomologous to a noncritical site in the mouse genome. The cloned DNA is introduced into a fertilized oocyte. The gene of interest inserts into the noncritical site by homologous recombination.

If a nucleus that was used to create cloned sheep came from a black faced ram instead of a white faced ewe as was used to create Dolly what would be the results?

The lamb would have a black face and be male

One potential problem with producing eukaryotic proteins in bacteria is that ____________.

The proteins may not be folded appropriately

Although Dolly was only three years old, her chromosomes had the length of a 9-10 year old sheep. Why could this have occured?

The telomeres of the somatic cells that Dolly originated from were shortening.

What is the purpose of breeding mice to homozygosity to generate knock-out mice?

To determine the function of a gene and they can be used for potential mouse models for human disorders.

A gene from one species that is introduced into another species is called a(n) _______________.

Transgene

What is the term for an organism that has received genetic material from a different species?

Transgenic organism

Describe an example of molecular pharming where you clone a hormone gene adjacent to b-lactoglobulin promoter.

Using recombinant DNA technology, clone a human hormone gene next to a sheep β-lactoglobulin promoter. This promoter is functional only in mammary cells so that the protein product is secreted into the milk. Inject this DNA into a sheep oocyte. The plasmid DNA will integrate into the chromosomal DNA, resulting in the addition of the human hormone gene into the sheep's genome. Implant the fertilized oocyte into a female sheep uterus, which then gives birth to a transgenic sheep offspring. Obtain milk from female transgenic sheep. The milk contains a human hormone. Purify the hormone from the milk.

An advantage of the ______________ approach is that there is efficient entry into the genome.

Viral

In the ____________ approach, a retrovirus is taken up by cell through endocytosis. The virus enters the cell through ectopic integration. The viral coat disassembles and RNA moves into the cytosol. RNA is transcribed to DNA through reverse transcriptase.

Viral

By adding the green fluorescent protein (GFP) gene next to a promoter that turns the gene on in the presence of certain environmental toxins, GloFish can be used to detect ______________ pollution.

Water

Research efforts in gene therapy are aimed at?

•Alleviating inherited diseases •Treating diseases such as cancer and heart disease •Combating infectious diseases such as AIDS