immortality as an engineering problem

Olaf Henny olafh at direct.ca
Sun Jul 19 18:19:43 EST 1998


Hi Thomas:

There is a company in Vancouver B.C., Canada, which 
actually produces and markets artificial chromosomes c/w 
telomeres, a product and technology, which may well have 
significance in the upcoming research of Lifeline 
Laboratories Inc.

Their website is: <http://www.chromos.com/index.html>

Here are some excerpts:

-  Mission:

"Smart Chromosomes.
Functional by Design."

Chromos Molecular Systems
Inc., is the world leader in the
development and commercial
application of artificial
chromosome technologies which
enable the controlled delivery
and long-term, stable expression
of large, single or multi-gene

-  Technology:

Why are mammalian artificial chromosomes important?
Current techniques for inserting new genetic material 
into cells to create transgenic animals or carry out 
gene therapy in humans - are still at an early stage of 
development. Whether genes are microinjected into a 
cell or carried into cells by specially adapted 
viruses, there is little control over where they go. 
This lack of control of the transfection of genetic 
can be transferred to the nucleus of the cell are 
partially responsible for the disappointing efficiency 
of current transgenic technologies and results of human 
gene therapy trials. The attraction of mammalian 
artificial chromosomes is that instead of being 
inserted at random into the existing chromosomes of a 
cell, new genes could be engineered in a separate 
chromosome with its own machinery for maintenance and 
replication. In addition, artificial chromosomes can be 
tested for functionality and stability prior to their 
use in target cells.

For mammalian artificial chromosomes to function as 
independent, stable, self-replicating gene carriers and 
expression platforms in the nucleus of the cell, they 
must contain certain key functional elements, such as a 
centromere, origins of replication and telomeres. They 
must also be neutral, i.e., carrying no unknown, but 
expressing, DNA, so as not to interfere with the 
expression of the marker/ therapeutic genes they carry, 
or with the functioning of the cell itself.

-  How mammalian artificial chromosomes are made 

Today, there are several groups in the world whose 
research is aimed at making mammalian artificial 
chromosomes. These chromosomes are not to be confused 
with yeast artificial chromosomes which are useful for 
helping deliver DNA into cells. While yeast chromosomes 
are useful research tools, they do not replicate in 
mammalian cells and therefore cannot be used as gene 
delivery vectors.

Research groups are using different strategies to make 
self-replicating artificial chromosomes. Most of these 
are in the experimental stage. 

The "top down" approach takes existing chromosomes and 
breaks them up into smaller sizes using various 
techniques. 

The "bottom up" approach takes component parts of mouse 
or human chromosomes and inserts them into a cell, 
thereby allowing the cell mechanism to assemble them 
back together to form an artificial chromosome. 

A third approach takes various elements from viruses, 
transfers them into cells and they assemble themselves 
as extrachromosomal elements independent from the 
cellular machinery. These are different from the two 
other approaches in that they do not contain 
centromeres but function outside the chromosome. For a 
detailed scientific explanation of these different 
approaches, see Nature Biotechnology, vol. 15, Vos,

"The simplicity of complex MACs". 

A fourth approach is Chromos' SATAC artificial 
chromosome.

-  How Chromos' SATACTM artificial chromosomes are 
made...


Best,

Olaf..

___________________________________

Tolerance is wisdom's finest fruit
___________________________________





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