WAS and immune system disorder: Affected individuals have small platelets with mild eczema and immunodeficiency, if any.[9] Mutations in the GBD domain of WASp lead to X-linked neutropenia characterized by congenital neutropenia, myeloid dysplasia, and lymphoid cell abnormalities.[10] Since X-linked neutropenia does not have the traditional WAS phenotype of thrombocytopenia and eczema, it should be differentiated from XLT and WAS.