By definition,<unk>  immune deficiencies are due to genetic causes. They may result from a single genetic defect, but most are multifactorial. They may be caused by recessive or dominant inheritance. Some are latent, and require a certain environmental trigger to become manifest, like the presence in the environment of a reactive allergen. Other problems become apparent due to aging of bodily and cellular maintenance processes.
Primary immunodeficiency
Combined immunodeficiencies
Severe combined immunodeficiency
Selective immunoglobulin A deficiency
Common variable immunodeficiency
IgG deficiency
X-linked agammaglobulinemia
Adult-onset immunodeficiency syndrome