DNA Articles du Jour

Next-generation pathogen sequencing

http://www.technologyreview.com/Biotech/20191/

454 Life Sciences have figured out how to isolate pathogen RNA from human tissue samples, and have used the process to identify previously-unknown pathogens as the likely cause of death for three transplant recipients.

In the 1980s, my brother's neighbor almost died from an illness whose cause was never determined. More recently, local doctors have been unable to figure out why a friend's daughter had a fever for three weeks. This process may make it possible to diagnose the causes of many more illnesses.

"...the sequence of the new virus was different enough that existing methods could not have detected [it]..."

"As many as 40 percent of cases of central nervous system disease cannot be traced back to a specific culprit. For respiratory illness, the figure is 30 to 60 percent."

"Usually, PCR requires some advance knowledge of the sequence in question because it relies on molecular primers that match the string of code to be amplified. But 454 sequencing avoids that problem by using a large number of random primers."

Combining DNA from >2 "parents"

http://www.dailytech.com/article.aspx?newsid=9835

I didn't know people could have problems with their mitochondrial DNA.

"...[the] research involved implanting the DNA from a [woman] with a mitochondrial disorder into the egg of a [woman] with healthy mitochondria. Thus the woman with the genetic disorder passed on the rest of her genetic legacy, while the other woman contributed only [healthy mitochondrial] DNA."

Ethical firestorm to follow...