Hoyeraal-Hreidarsson syndrome

Hoyeraal-Hreidarsson syndrome (HHS) is a very rare multisystem X-linked recessive disorder characterized by excessively short telomeres and is considered a severe form of dyskeratosis congenita. Being an X-linked disorder, HHS primarily affects males. Patients with HHS typically present in early childhood with cerebellar hypoplasia, immunodeficiency, progressive bone marrow failure, and intrauterine growth restriction. The primary cause of death in HHS is bone marrow failure, but mortality from cancer and pulmonary fibrosis is also significant. Hoyeraal-Hreidarsson syndrome (HHS) is a very rare multisystem X-linked recessive disorder characterized by excessively short telomeres and is considered a severe form of dyskeratosis congenita. Being an X-linked disorder, HHS primarily affects males. Patients with HHS typically present in early childhood with cerebellar hypoplasia, immunodeficiency, progressive bone marrow failure, and intrauterine growth restriction. The primary cause of death in HHS is bone marrow failure, but mortality from cancer and pulmonary fibrosis is also significant. The currently recognized features of HHS are cerebellar hypoplasia, immunodeficiency, progressive bone marrow failure, and intrauterine growth restriction. HHS patients also commonly exhibit symptoms such as microcephaly, aplastic anemia, and intellectual disability. In addition to HHS-specific sequelae, HHS patients frequently present with the mucocutaneous triad of nail dysplasia, lacy skin pigmentation, and oral leukoplakia Although the pathogenesis of HHS remains unknown, it is strongly suspected that the clinical sequelae of HHS arise from the accelerated telomere shortening present in HHS patients. It has been associated with mutations in the poly(A)-specific ribonuclease PARN gene. Current treatment is supportive. TeloCure Ltd. TeloCure Ltd. is developing gene therapy solutions for HHS. The company is funded by the foundation for Noga Baumatz and other HHS patients which was founded by the family of a deceased HHS patient.