HNRNPH2 Genetics 101
How does the disorder resulting from the HNRNPH2 mutation affect the individual?
Heterogeneous nuclear ribonucleoprotein H2 (HNRNPH2) is a gene in humans. HNRNPH2 genetic mutations result in a neurodevelopmental phenotype including developmental delay, intellectual disability, hypotonia, and seizures, among other characteristics. This was first identified in “Variants in HNRNPH2 on the X chromosome are associated with a neurodevelopmental disorder in females” by Drs. Jennifer Bain and Wendy Chung, published in the American Journal of Human Genetics in September 2016. In 2016, 6 girls were identified with variants in the HNRNPH2 gene in a study by Dr. Jennifer Bain, Pediatric Neurologist at Columbia University. She found that each individual had developmental delay or intellectual disability, as well as atypical muscle tone. Many of the girls also experienced seizures and conditions such as anxiety and autism spectrum disorder (ASD). They discovered variants in HNRNPH2 also seemed to affect other organ systems in the body aside from the brain. For instance, patients with variations in HNRNPH2 also had problems with growth, gastroesophageal reflux disorder, scoliosis and other skeletal problems, heart problems, and atypical facial features.
Each year more and more patients are identified. Currently, there are just under 80 cases known around the world and Yellow Brick Road Project has connected with over 55 families!