Stanford Collaborates with Pacific Biosystems to Carry Out Long-Read Sequencing to Confirm Diagnosis of Very Rare Mendelian Disease; First Use of Long-Read Sequencing in Clinical Setting Is in Synch with Stanford’s Focus on Precision Health

When Ricky Ramon was 7, he went for a routine checkup. The pediatrician, who lingered over his heartbeat, sent him for a chest X-ray, which revealed a benign tumor in the top-left chamber of his heart. For Ramon, it was the beginning of a long series of medical appointments, procedures, and surgeries that would span nearly two decades. During this time, noncancerous tumors kept reappearing in Ramon's heart and throughout his body -- in his pituitary gland, adrenal glands above his kidneys, nodules in his thyroid. When Ramon was 18, doctors thought his symptoms were suggestive of Carney complex, a genetic condition caused by mutations in a gene called PRKAR1A. However, evaluation of Ramon's DNA revealed no disease-causing variations in this gene. Now, eight years later, researchers at the Stanford University School of Medicine have used a next-generation technology -- long-read sequencing -- to secure a diagnosis for Ramon. It is the first time long-read, whole-genome sequencing has been used in a clinical setting, the researchers report in a paper published online on June 22, 2017 in Genetics in Medicine.