Study finds genes associated with bleeding disorder caused by low platelets

Researchers at Baylor College of Medicine have found genes associated with an autoimmune bleeding disorder called chronic immune thrombocytopenia, or ITP.

HOUSTON - (Dec. 7, 2015) - Dr. Jenny Despotovic, assistant professor of pediatrics at Baylor and Texas Children’s Cancer and Hematology Centers, presented the research Dec. 5 at the American Society of Hematology 57^th Annual Meeting.

ITP is an autoimmune disorder in which antibodies are formed against platelets, resulting in a low platelet count and blood that does not properly clot, increasing the risk of bleeding, which can be severe and even life threatening. The study sought to identify genetic variants associated with susceptibility to and severity of the disease.

Researchers obtained DNA samples from the North American Chronic ITP Registry and the Platelet Disorders Center at the Weill-Cornell Medical Center, and whole exome sequencing was performed at Baylor College of Medicine’s Human Genome Sequencing Center. This work was done as a collaboration with the ITP Consortium of North America, of which Baylor and Texas Children's Hospital have been key participants since its inception. 

“Results of the study showed that variants in genes associated with immune cell signaling, including IFNA17, are significantly more common in children with chronic ITP than in the healthy population,” Despotovic said. 

Of the 172 ITP patients in the study, more than 40 percent had a variant in IFNA17, including one variant present in 26 percent of the ITP patients compared to about 5 percent of controls. This gene is associated with immune cell activity, and could have an important role in predisposition to ITP or disease severity. 

“We also identified genes, including DOK3, that are far more common in children with ITP who required more aggressive treatment than those who did not,” Despotovic said.

“This study is the first of its kind in chronic ITP, and these findings may facilitate improved understanding of the development of this disease and why it becomes a chronic disease in some children,” she said. “In addition, understanding patients’ genetic changes could lead to more personalized approaches to treatment of this disorder.” 

Others who contributed to this research included Eric Boerwinkle and Linda Polfus, both of the University of Texas Health Science Center at Houston, Jonathan Flanagan of Baylor and Texas Children’s Hospital, as well as numerous collaborators in ICON. 

About Texas Children’s Hospital

Texas Children’s Hospital, a not-for-profit health care organization, is committed to creating a healthier future for children and women throughout the global community by leading in patient care, education and research. Consistently ranked as the best children’s hospital in Texas, and among the top in the nation, Texas Children’s has garnered widespread recognition for its expertise and breakthroughs in pediatric and women’s health. The hospital includes the Jan and Dan Duncan Neurological Research Institute; the Feigin Center for pediatric research; Texas Children’s Pavilion for Women, a comprehensive obstetrics/gynecology facility focusing on high-risk births; Texas Children’s Hospital West Campus, a community hospital in suburban West Houston; and Texas Children’s Hospital The Woodlands, a second community hospital planned to open in 2017. The organization also created the nation’s first HMO for children, has the largest pediatric primary care network in the country and a global health program that’s channeling care to children and women all over the world. Texas Children’s Hospital is affiliated with Baylor College of Medicine. For more information, go to www.texaschildrens.org. Get the latest news by visiting the online newsroom and Twitter at twitter.com/texaschildrens.