W Introduction to Gene Therapy and Therapeutic Cloning Flashcards
Differentiation results from ?
differential gene
expression.
What does the Nuclear transplant and cloning experiments show .?
differentiated cell nucleus can retain totipotency and have the ability to act like a zygote nucleus and stimulate the production of an entire organism.
Dolly sheep camefrom?
3 mothers
Example of mammals that have been cloned?
mice,
rats, cows, pigs, goats, cats and even a horse!
How to make nerve cells from ESCs?
Treatment of ESCs with a derivative of vitamin A
causes them to form nerve cells.
Meaning of somatic cell nuclear transfer (SCNT)?
Transfer the nucleus from a normal patient cell to an
enucleated egg.
Ways to Obtain Pluripotent Stem Cells?
Emberyonic stem cells
Induced pluripotent stem cells
What is NOT permitted of SCNT?
✓ Embryo development beyond 14 days
✓ Embryo implantation into a woman’s or animal’s
body
✓ Production of embryos by egg and sperm for
research
Why SCNT: Not yet achieved for humans?
Due to inefficiency of NT, and limited availability of eggs (ethical issue).
Alternatives of SCNT?
• Use adult stem cells.
• Convert ‘ordinary’ cells to cells having stem cell
properties.
Where we can found Adult Stem Cells (ASC)?
Found in tissues such as brain, bone marrow, skin, intestine
(all tissues?) being responsible for their replenishment
Cells isolated from human fat (gives us )?
removed by liposuction) were shown to develop into muscle, bone and cartilage
What are the Limits of ASC Potential?
1-the environment of stem cells limits their ability to specialise
2-cell’s
environment determines what an adult stem cell will do.
Ways of Converting ‘Ordinary’ Cells to stem cells ?
a -classical development and hESC derivation.
b-standard nuclear transfer
How many genes coding in the Reprogramming Mouse Skin Cells
?
4 genes
Rapid Advances Using iPS Cells .?
Successful treatment of mouse sickle cell anaemia by iPS from autologous skin (2007)
• Human iPS cells (2007-8)
• Creation of virus-free human iPS cells (2009) • iPS cells are generated from disease cells.
)
✓ 82 year-old patient with amyotrophic lateral sclerosis (ALS); made iPS
cells and directed them to form motor neurons the cell type destroyed
in ALS
Why Recent Reports Call for Caution of ips?
Epigenetic differences
Genomic abnormalities:
Which type of disease Human Gene Therapy (HGT) treat ?
homozygous for a recessive mutation
lacking a functional gene product.
inherited disease
but includes cancer and infectious diseases.
Current gene therapy practice involves?
addition NOT correction or replacement.
First Clinical Trial of Gene Therapy
1990
Ashanti )م adenosine
deaminase (ADA) deficiency.
infected with a normal ADA gene in retroviral vector.
Cancer vector ?.
oncolytic adenovirus vectors
First Trial For A Haemoglobin Disorder Using which vector ?
Lentiviral Vector
Improvements in Gene Delivery are Still Needed.?.
• Specificity and improvement of gene transfer.
• Specificity, magnitude and duration of gene
expression.
• Avoiding stimulation of the immune system by some
vehicles.
• Manufacturing problems.
n.b. There is no ideal delivery vehicle for all applications.
X-linked adrenoleukodystrophy (ALD) is a
neurodegenerative disease caused by?
mutation in the ABCD1 gene.
