Application of gene technology

tanktherapistBiotechnology

Oct 23, 2013 (3 years and 11 months ago)

73 views

Application of gene technology

Transgenic organisms and
gene
therapy

Unit 4, AOS 2

Marina Kalcina

What do you think of when you look at this picture?

By the end of today’s lesson you will know
about one aspect of gene technology & be
able to:


Describe

the

different

ways

transgenics

are

made


L
ist

examples

of

transgenic

organisms


Explain

how

gene

therapy

works

and

list

diseases

for

which

it

has

been

used


Debate

issues

surrounding

the

use

of

transgenic

organisms

and

gene

therapy


Artist: Patricia
Piccinini

http://
www.patriciapiccinini.net
/

How are transgenic organisms made?

Getting genes into animal cells

A

transgenic

organism

is

one

in

which

a

foreign

gene

has

been

inserted

into

it’s

genome

to

enable

production

of

a

specific

protein
.

There

are

4

main

ways

transgenics

can

be

made

in

animals
:



Microinjection


Electroporation


Fusion

of

vesicles


Gene

gun

Microinjection

A glass micropipette is used to puncture a hole in the cell
and nuclear membranes and insert the genes.


Allows only one cell to be treated at a time

Electroporation

A short electric shock makes many cells permeable at the same time.


This allows the DNA to enter the cell


What does permeable mean?


How is electroporation different to microinjection?

Fusion of vesicles

Vesicle is created where desired DNA is enclosed in a membrane.


Vesicle membranes fuse with cell membranes and DNA enters the
cell.


The vesicles can be made to fuse with many cells at a time.

Gene gun

Gold or other metallic particles are coated with DNA of interest


The DNA covered metallic particles are then fired into the
nucleus of a cell using a gene gun

How have bacterial
transgenics

helped
us?



http
:
//www
.
biotechnologyonline
.
gov
.
au/biotechnologyonline/pop
ups/
int_splicing
.
html


Insulin

is

a

hormone

diabetics

need

to

inject

every

day



Too

complex

to

be

made

in

the

lab


Limited

amounts

used

to

be

obtained

from

pancreas

of

animals

being

slaughtered

for

food


The

human

insulin

producing

gene

was

placed

in

a

bacterial

plasmid,

bacteria

reproduced

and

made

few

billion

copies

of

itself


Insulin

extracted

from

bacteria

for

medical

use


The

animation

above

allows

students

to

explore

this
.


Ask

students

to

make

a

flow

chart

after

working

through

the

animation


Some examples of
transgenics


GFP animals from the start


Bacteria used for insulin and some vaccines


Sheep with a human gene which causes their
milk to contain a blood
-
clotting protein which
can then be extracted from milk to treat
humans


Silk worms that produce human collagen


Many examples


get students to research
more and present them?


Gene therapy

Gene

therapy

is

the

technique

of

delivering

normal

and

fully

functional

genes

to

individuals

to

compensate

for

a

disease

causing

mutation
.

It

has

the

potential

to

treat

or

cure

people

suffering

from

a

range

of

genetic

conditions
.



The

functional

gene

has

to

be

located,

isolated

and

cloned

in

sufficient

quantities

and

a

suitable

vector

needs

to

be

found

to

deliver

the

gene
.


The

inserted

gene

needs

to

be

able

to

persist

and

function

normally

within

the

target

cells




Gene therapy procedure and examples


AIDS


Cystic
fibrosis


Cancer


Parkinson’s


Alzheimer’s


Arthritis

Somatic cell vs. germ
-
line gene
therapy

Somatic

cell

gene

therapy
:



T
he

process

talked

about

so

far


Alters

the

genotype

of

somatic

cells


Extremely

difficult

to

insert

new

genes

into

every

cell

or

organ


The

healthy

gene

cannot

be

passed

onto

offspring

Germ
-
line

gene

therapy
:


Transformation

of

eggs

or

sperm


The

healthy

genotype

will

be

passed

onto

offspring


Extremely

controversial


Not

an

accepted

medical

practice


Questions and activities to ask students to
stimulate thinking in the higher order


What

do

you

think

would

be

some

risks

associated

with

gene

therapy?


Write

down

some

arguments

‘for’

and

‘against’

gene

therapy
.


Organise

debates
!

Split

the

class

in

half
.

One

half

will

argue

for

transgenic

organisms,

the

other

half

will

argue

against

them
.


Debate
:

Is

a

tomato

injected

with

an

arctic

fish

gene

to

prevent

it

from

frosting,

still

a

tomato?

Or
,

is

the

transgenic

tomato

still

a

suitable

food

for

vegetarians?

Another activity:

Present

the

following

scenario
:



Any

gene

researcher

conducting

experiments

in

an

institute

needs

to

have

approval

from

the

biosafety

and

bioethics

committee
.

Imagine

a

research

team

is

applying

for

permission

to

develop

a

particular

transgenic

organism

.



Split

the

students

into

groups

of

5


Allocate

the

role

of

committee

to

2

or

3

members

of

the

group
.


Allocate

the

role

of

research

applicants

to

2

or

3

members

of

the

group



Higher order thinking activity
continued….

Some points students may want to discuss in their groups:

Researchers

Committee members

Name

of the company for
which you want to develop
the transgenic organism?

What guidelines

are the
researchers to follow to
ensure:


卡f整e 瑯 r敳敡rch敲s in
lab


卡f整e 瑯 敮vironm敮t


E瑨ical issu敳 ar攠
addr敳s敤?

Wha琠瑲ansg敮ic organism
would you lik攠瑯

d敶敬op
and why?


What

sor瑳 of qu敳瑩ons
will b攠ask敤 of 瑨攠
r敳敡rch敲s?

䡯w will w攠r敳pond


qu敳瑩ons 瑨攠commi瑴敥
has?


Once

students

have

had

time

to

talk

about

the

points

listed

in

the

table,

ask

them

to

present

their

findings

in

a

group

role
-
play



Members

of

the

audience

(rest

of

the

class)

can

help

the

committee

decide

whether

to

agree

to

the

researchers’

proposal

References and resources:


ScienceAlert

facebook

page


Science Quest 4 textbook, Lofts & Evergreen 2007


Nelson Biology textbook, VCE units 3 & 4, Borger et al,
2006


Spotlight Biology textbook, VCE units 3 & 4, Joanne
Burke, 2007


Biotechnology online for the
animation:
http
://www.biotechnologyonline.gov.au
/
biotechnologyonline
/popups/int_splicing.html


Google images