The Deficiency of Adenosine Deaminase 2 (DADA2) (OMIM: 607575) is a monogenic, autoinflammatory disease caused by the loss of functional homozygous or heterozygous mutations in the ADA 2 gene (previously CECR1 Cat Eye Syndrome Chromosome Region 1) [1,2]. This evidence concerns the gene ADA2 and cat-eye syndrome.