When Luke Terrio was about seven months old, his mother began to realize something was off. He had constant ear infections, developed red spots on his face, and was tired all the time. His development stagnated, and the antibiotics given to treat his frequent infections stopped working. His primary care doctor at Children's Hospital of Philadelphia (CHOP) ordered a series of blood tests and quickly realized something was wrong: Luke had no antibodies. At first, the CHOP specialists treating Luke thought he might have X-linked agammaglobulinemia (XLA), a rare immunodeficiency syndrome seen in children. However, as the CHOP research team continued investigating Luke's case, they realized Luke's condition was unlike any disease described before. Using whole exome sequencing to scan Luke's DNA, CHOP researchers discovered the genetic mutation responsible for his condition, which prevents Luke and patients like him from making B cells and antibodies to fight infections. The study describing Luke's condition, which CHOP researchers, together with colleagues, named PU.1 mutated agammaglobulinemia (PU.MA), was published online on May 5, 2021 in the Journal of Experimental Medicine. The article is titled “Constrained Chromatin Accessibility in PU.1-Mutated Agammaglobulinemia Patients” (https://rupress.org/jem/article-abstract/218/7/e20201750/212070/Constrai...). "It can be pretty scary for a family whose child has a mysterious illness" said Neil D. Romberg, MD, an attending physician with the Division of Allergy and Immunology at CHOP and senior author of the paper. "In this case, science provided an explanation, thanks to numerous departments at CHOP, including the Roberts Individualized Medical Genetics Center, the Center for Spatial and Functional Genomics, and the Cancer Center. Understanding the cause of Luke's condition absolutely helped us know what direction to take his therapy."Login Or Register To Read Full Story