Autosomal recessive TPP2 mutations cause a new human immunodeficiency

To define a genetic syndrome of combined immunodeficiency, severe autoimmunity, and developmental delay, 4 patients from two families who had similar syndromic features were studied. To identify disease-causing mutations, we performed whole exome sequencing for one patient and her healthy parent from Family 1 and also for one patient from Family 2. Disease segregated with novel autosomal recessive mutations in a single gene, tripeptidyl-peptidase II (TPP2) gene. The result defines a new human metabolic immunodeficiency.]]> Patient samples were chosen for inclusion in the project based on the following criteria: Families who had similar syndromic features were studied. Patients, parents and other family members are available. DNA was available for use in exome sequencing. Informed consent documentation. ]]>