MGI:97616Homozygotes for some null alleles show decreased B cell and impaired NK cell function. Other homozygous null alleles show aberrant separation of blood and lymphatic vessels. A point mutation associated with Alzheimer's disease protective effect leads to enhanced intracellular Ca2+ release in response to various stimuli in microglia and reduced phagocytosis and enhanced endocytosis in microglia and macrophages.