Medical Biotechnology. Chapter 11. Testing for Down’s Syndrome and sex. “Karyotyping”. Screening for genetic abnormalities. Fluorescent in situ hybridization (FISH) used to detect: Extra chromosomes Missing parts of chromosomes DNA swapping across different chromosomes
Fluorescent DNA probes
Oligonucleotide probes that react with sequence of normal bA gene or disease bS gene
Normal gene sequence
Disease gene sequence
Add probe for
Add probe for
Probe for normal gene
Probe for disease gene
Insulin delivered as a powder through an inhaler
A B A,B O
Out of 100 donors . . . . .
Severe combined immune deficiency
Mutation in gene encoding
adenine deaminase enzyme
Shows up as incompetent
T-cells which prevent B-cells
from making antibodies
Drill hole in skull
Pigs genetically engineered to lack a sugar-producing gene that causes human bodies to reject pig organs
Embryonic Stem Cells
Subject stem cells to specific conditions to encourage differentiation into one of many cell types
What stages of early embryonic development are
important for generating embryonic stem cells?
Embryonic stem cells, as their name suggests, are derived from embryos. Specifically, embryonic stem cells are derived from embryos that develop from eggs that have been fertilized in vitro in an in vitro fertilization clinic and then donated for research purposes with informed consent
of the donors.
They are not derived from eggs fertilized in a woman's body.
The embryos from which human embryonic stem cells are derived are typically four or five days old and are a hollow microscopic ball of cells called the blastocyst.
Step 1- Define the problem.
Brain and spinal cord injuries result in damage to neurons.
Damaged neurons are not replaced by the right kind of newborn neurons
Parkinson’s Disease is a genetic defect that results in dead nerve cells that do not produce sufficient amounts of dopamine needed for normal nerve signaling
Step 2: Determine source of stem cells
Stem cells from another normal individual or stem cells from patient?
Step 3: Determine source of stem cells
If source is from patient’s previously collected and stored stem cells, use these
If patient has Parkinson’ Disease, then introduce good copy of gene in chromosome of stem cells
The implanted cells must survive and differentiate into the proper nerve cells (medium –sized spiny neurons in case of injury or dopamine-producing cells in case of Parkinson’s Disease patient.
Some patients reported a lessening in the severity of their symptoms.
Some patients who underwent the procedure experienced severe side
effects, including involuntary muscle twitching and jerking.