Nina Gold, MD, is Chief Resident of Medical Genetics at Boston Children’s Hospital.
During a quiet stretch of my final year in medical school, I read Sir Arthur Conan Doyle’s Sherlock Holmes stories. A master observer, the detective found secrets in wrinkles of clothes, tints of hair, scents of perfume, never satisfied until the truth was revealed. Sherlock was, simply, an expert diagnostician.
In the spring of 2014, I became the first student in my medical school to pursue residency training in a combined pediatrics and medical genetics program. Like Sherlock, pediatric geneticists are stalwart investigators. They are often called into a case long after other consultants and tasked with bringing a family’s diagnostic odyssey to an end. But unlike the emotionally obtuse fictional detective, geneticists must describe their findings with empathy and clarity to concerned families after they solve a mystery. …
Some 7,500 rare disorders are known to be caused by single-gene mutations. Most of these disorders first appear at birth or in childhood, and for about half, the responsible gene has been identified. Yet, on average, families with rare disorders spend 12 years searching before getting a correct diagnosis.
Jackie Smith, a 35-year-old mother of two, searched for 32 years for the cause of her muscular weakness. Her parents knew something was wrong soon after she was born. At first, because her ankles turned in, they thought she was bow-legged. …
The CLARITY Undiagnosed Challenge is heating up. Biomedical teams from seven countries are racing to interpret DNA sequences from five families affected with undiagnosed illnesses—some with gravely ill children, some already bereaved, all desperate for answers.
In July, the 26 competing teams received whole-genome and whole-exome sequence data from each patient and close family members, along with clinical notes and patient videos. Their reports, due September 21, will be judged by an independent panel based on:
- the methods used to analyze and interpret the sequence data
- the ability to synthesize the information
- clinical usefulness, care recommendations and “next steps.”
One of a series of posts honoring #RareDiseaseDay (Feb 28, 2015).
Historically, the starting point for making a rare disease diagnosis is the patient’s clinical profile: the set of symptoms and features that together define Diamond Blackfan anemia (DBA), Niemann-Pick disease or any of a thousand other conditions.
For example, anemia and problems absorbing nutrients are features of Pearson marrow pancreas syndrome (PS), whereas oddly shaped fingernails, lacy patterns on the skin and a proneness to cancer point to dyskeratosis congenita (DC).
The resulting diagnoses give the child and family an entry point into a disease community, and is their anchor for understanding what’s happening to them and others: “Yes, my child has that and here’s how it affects her. Does it affect your child this way too?”
But as researchers probe the relationships between genes and their outward expression—between genotype and phenotype—some families are losing that anchor. They may discover that their child doesn’t actually have condition A; rather, genetically they actually have condition B. Or it may be that no diagnosis matches their genetic findings.
What does that mean for patients’ care, and for their sense of who they are? …
The Human Genome Project’s push to completely sequence the human genome ran a tab of roughly $2.7 billion and required the efforts of 20 research centers around the world using rooms full of equipment.
But that was using technology from the 1990s to early-2000s. As by a panel of genomics experts from industry and academia pointed out at last week’s National Pediatric Innovation Summit + Awards, a scientist in a single laboratory today can sequence a genome for as little as $1,000, making sequencing almost a medical commodity.
Now what? How do we go about making clinical genomics an everyday thing? The discussion left the answer to that question—and the other questions it raises—unclear. While the panelists expressed excitement about what’s possible, they cited great uncertainty among doctors, scientists, patients, payers, companies and regulators about how to make clinical genomics work. …