to:

• Each Gene can be individually transcribed to make a RNA version of itself.

• The RNA version may have a function, or it may be used to encode a protein which has the function.

-transcription occurs in nucleus, forms mRNA

-The mRNA is transported to the cytoplasm for protein synthesis to occur.

-Transfer RNA (tRNA)

• Carries amino acids

• Matches its complementary anticodon with codons on mRNA

• Codons are three nucleotides long

Genetic code: allows a specific codon to code for a specific amino acid

• A codon is composed of three nucleotides.

• 61 codons code for amino acids.

• 3 others are stop codons (Stop signs), which end protein synthesis.

• Almost every organism on earth uses the exact same code to turn DNA into protein!

• Every cell of our body has 2 copies of every single gene.

• Not every gene is used in every cell (differential expression)

Regulation of transcription

• Activators regulate (Turn on) gene expression

• Used by eukaryotic cells

• Help the RNA polymerase bind to the promoter

• Repressors regulate (Keep off) gene expression

• Used by prokaryotic cells

• Bind to the promoter and prevent the RNA polymerase from binding

Genetic Modification

•Any gene can be amplified and isolated.

•We can also amplify and isolate any on/off switch that is needed.

-Plasmid – A circular piece of DNA that can be replicated by bacteria, and carry genes that will be made into proteins.

•Recombinant: genetically engineered; a gene that has been removed from its original genome and combined with another.

Stem cells: unspecialized, undifferentiated precursor cells with an undetermined function

•Totipotent: can become any cell type in the body

•Embryonic Stem Cells: Totipotent cells derived from a very early embryo.

•Adult stem cells: found in nonembryonic tissue

•Umbilical cord blood

•Bone marrow

Stem Cells

•Mitotic cells that have the ability to reproduce themselves, but can also produce other types of

cells.

•As cells develop from Stem cells to functional mature cells they lose the potential to become other types of cells.

•“the FDA has approved umbilical cord blood therapies for cancer or immune disorders”.

•Commonly practiced without approval: To replace stem cells that have been removed due to chemical or radiation treatment.

•bone marrow is a source of adult derived stem cells

Sources of Stem Cells

•Induced Pluripotent Stem Cells are have supplanted the need to harvest cells

from embryonic tissue.

•IPSCs preferred because less chance your body will reject them.

-iPSC are derived from skin or blood cells that have been reprogrammed back into an embryonic-like pluripotent state that enables the development of an unlimited source of any type of human cell needed for therapeutic purposes (used for diabetes,leukemia, etc.)

Genetic Modification

Gene therapy: replacement of defective genes with functional genes

•Somatic cell gene therapy: fixes or replaces the defective protein only in affected cells

Genetic Modification

•Rare x- linked disorder – could not metabolize ammonia.

•Participated in one of the first trials.

•Died 3 days after the first treatment, as the virus cause a serve immune reaction the cause multiple organ failure and brain death.

Genetic Modification

•Fixing children with defective immune systems.

•Pull the cells out, and screen them prior to reinsertion.

•Many years of intense follow up.

.CRISPR/CAS9

•Allows researchers to specifically target 1 gene and cut the DNA at that location.

•Uses DNA repair proteins in the patient to make the repair; however, sometimes it makes a mistake causing mutations.

•Embryo subdivides into two separate embryos early in development.

•Nuclear transfer: process used for cloning where an adult cell nucleus is fused with an egg cell