Natural History Study of GATA2 Deficiency and Related Disorders

Background: \- GATA2 deficiency is a genetic disorder that can cause problems with a person s immune system and other body systems. Some people who have this disorder develop few problems from it. Others can have a wide range of health problems, from skin problems, to hearing loss, to cancer. These problems can happen at any age. Researchers want to study GATA2 deficiency to better understand what types of health problems it can cause, and why it causes problems in some people but not others, and at different ages. Objectives: \- To improve understanding of GATA2 deficiency so there can be better diagnostic tests and treatments in the future. Eligibility: \- People 2 years of age or older who have a GATA2 gene mutation or certain health conditions that are commonly seen in people with this mutation and their blood relatives. Design: * Participants will be screened with a physical exam and medical history. Blood and urine samples will be collected to see whether participants have the GATA2 genetic mutation. Several other tests may be recommended, but participants can decline to take them. * Participants will be eligible to receive standard care for GATA2 deficiency through this protocol. They may be eligible for other clinical trials at the National Institutes of Health as well. * Participants will have regular study visits once a year to evaluate their GATA2 deficiency. Participants will take part in the study for at least 3 years and up to 15 years. At these follow-up visits, participants will fill out a questionnaire and take a physical exam and blood tests. Other tests may be performed as needed.