Microsoft Word Kurzweil, Ray The Singularity Is Near doc

RNAi (RNA Interference).
A powerful new tool called RNA interference (RNAi) is capable of turning off specific 
genes by blocking their mRNA, thus preventing them from creating proteins. Since viral diseases, cancer, and many 
other diseases use gene expression at some crucial point in their life cycle, this promises to be a breakthrough 
technology. Researchers construct short, double-stranded DNA segments that match and lock onto portions of the 
RNA that are transcribed from a targeted gene. With their ability to create proteins blocked, the gene is effectively 
silenced. In many genetic diseases only one copy of a given gene is defective. Since we get two copies of each gene, 
one from each parent, blocking the disease-causing gene leaves one healthy gene to make the necessary protein. If 
both genes are defective, RNAi could silence them both, but then a healthy gene would have to be inserted.
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Cell Therapies.
Another important line of attack is to regrow our own cells, tissues, and even whole organs and 
introduce them into our bodies without surgery. One major benefit of this "therapeutic cloning" technique is that we 
will be able to create these new tissues and organs from versions of our cells that have also been made younger via the 
emerging field of rejuvenation medicine. For example, we will be able to create new heart cells from skin cells and 
introduce them into the system through the bloodstream. Over time, existing heart cells will be replaced with these 
new cells, and the result will be a rejuvenated "young" heart manufactured using a person's own DNA. I discuss this 
approach to regrowing our bodies below. 
Gene Chips.
New therapies are only one way that the growing knowledge base of gene expression will dramatically 
impact our health. Since the 1990s microarrays, or chips no larger than a dime, have been used to study and compare 
expression patterns of thousands of genes at a time.
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The possible applications of the technology are so varied and the 
technological barriers have been reduced so greatly that huge databases are now devoted to the results from "do-it-
yourself gene watching."
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Genetic profiling is now being used to: 
•
Revolutionize the processes of drug screening and discovery.
Microarrays can "not only confirm the mechanism 
of action of a compound" but "discriminate between compounds acting at different steps in the same metabolic 
pathway."
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•
Improve cancer classifications.
One study reported in Science demonstrated the feasibility of classifying some 
leukemias "solely on gene expression monitoring." The authors also pointed to a case in which expression 
profiling resulted in the correction of a misdiagnosis.
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•
Identify the genes, cells, and pathways involved in a process, such as aging or tumorigenesis.
For example, by 
correlating the presence of acute myeloblastic leukemia and increased expression of certain genes involved with 
programmed cell death, a study helped identify new therapeutic targets.
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•
Determine the effectiveness of an innovative therapy.
One study recently reported in Bone looked at the effect of 
growth-hormone replacement on the expression of insulinlike growth factors (IGFs) and bone metabolism 
markers.
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•
Test the toxicity of compounds in food additives, cosmetics, and industrial products quickly and without using 
animals.
Such tests can show, for example, the degree to which each gene has been turned on or off by a tested 
substance.
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