Genetic Testing to Diagnose Primary Immunodeficiency Disorders and to Identify Targeted Therapy.

Since the first genes associated with primary immunodeficiency were described in the early 1990s, there has been an exponential increase the number of genes found to have pathologic variants in patients with symptoms of primary immunodeficiency. Genetic testing currently used clinically includes chromosomal microarray, Sanger sequencing, and next-generation sequencing techniques, including whole exome testing. With the knowledge of the underlying molecular pathways, biologic therapies have been used for treatment and efforts are underway to broaden the availability of gene therapy.