No good percentages (29 days)

There are no good percentages when it comes to genetic disease.

I remember my first meeting with out genetic counselor. She was talking about recurrence and what could possibly be the cause of our first son’s amazingly long list of medical maladies. She was saying things like “autosomal recessive” and “dominant” and “de novo.” She was talking about this big test called the micro array and how it would likely find the problem.
I was so overwhelmed with my sorrow that the numbers sort of swam around in the air in that little office. Nothing stuck. My baby was going to die, so who cares about the percentage? He would be 100 percent dead eventually.
But those percentages have been swimming in front of me ever since. Obviously, our situation was NOT de novo — or a sort of genetic, one-time “fluke,” because it happened again with our second son. So, what are the percentages? Is it 25 percent? 50 percent? More?
Now I have a new percent, a number never mentioned by any genetic counselor or on any of the paperwork I signed for my second son’s exome. This exome from Baylor has a 30 percent chance of finding the genetic issue that killed my boys. 30 percent. That’s it.
How do I know? The Interweb told me so.
Another stunning late night read is Eliza Strickland’s piece for science journal Ieee Spectrum, where this normal, healthy woman gets her exome studied at Baylor to see what exactly her genetic code says. Her exome was just for fun, and she seems to have gotten something out of it, but I am more interested in the information AROUND her exome experience — a sneak peek into the lab at Baylor and the unveiling of a stunning new percentage — Baylor’s exome has a 30 percent diagnostic success rate.


Just 30 percent. All this wait, all this worry, all this obsession for 30 percent.


From the article:
Baylor opened a commercial lab in October 2011 to provide sequencing services for doctors grappling with tough cases — patients who are on “medical mystery tours,” as Lupski puts it. The lab has a 30 percent diagnostic success rate, which means doctors can pinpoint, in almost one-third of the cases, the mutations in a patient’s DNA that are causing symptoms. That rate may seem pretty low. But doctors consider it a remarkable achievement, given the sprawling complexity of any human’s DNA and how little is now conclusively known about how our genes function. As Lupski puts it, “in this branch of medicine, we admit our ignorance a lot more.”

Read more about Strickland’s exome experience here:
http://spectrum.ieee.org/biomedical/devices/the-gene-machine-and-me