In all the stories about the lowering cost of DNA sequencing, this NY Times contribution has to be the most heartbreaking: "Infant DNA Tests Speed Diagnosis of Rare Diseases". Yes, I know it doesn't sound like a heartbreaking headline, but the article is about end-of-life decisions for infants with undiagnosable congenital disorders.
Although genetic causes for the diseases were found in three of the four babies, the diseases had no treatments — except for surgery for the brothers — and that baby was the only one who survived.
The biggest surprise for Dr. Kingsmore, though, was that the families greatly valued having a diagnosis.
When a baby has a mysterious disease, he said, the family often embarks on a terrifying diagnostic odyssey. “Test after test is performed,” he said. “Some tests are invasive; the child is suffering. The child is getting worse and worse — most spend their entire lives in the hospital, and there is no answer.”
Just knowing the answer can be a comfort. “Providing a definitive diagnosis somehow brings closure,” Dr. Kingsmore said. “It is something they can name.”
Sequencing today is still quite expensive, and interpretation still is usually uncertain. These factors make some skeptics question whether whole-genome sequencing will ever find effective clinical applications.
The article describes a proof-of-concept study in which rapid whole-genome sequencing was applied to clinical pediatric cases, in some cases retrospectively. That area of medicine puts the question of cost and benefits of sequencing in a very different light: A day in newborn intensive care can cost $8000, at present the testing costs $13,500. Accurate information about a fatal genetic disorder can help parents and doctors call off heroic efforts, prevent extraneous and sometimes painful forms of non-genetic testing, and assure them that they have done everything possible for a child.
This is the hard edge of personalized genomics. It's not about whether you should cut back on LDL to lower your long-term cardiac risk. It's about when to end care of babies with no treatment options.