Response to JAK inhibition suggests that interferon hyperactivation underlies psoriatic arthritis in Down Syndrome.

Individuals with Down syndrome have widespread immune dysregulation, including an increased risk of autoimmune and autoinflammatory skin conditions, like alopecia areata. The triplication of chromosome 21 causes activation of a branch of the immune system called interferon, known to contribute to autoimmunity…..

It is well known that a third copy of chromosome 21 (trisomy 21) causes Down Syndrome; however, the molecular processes that occur as a result are not well understood. In this landmark publication, our scientists used complementary genomics techniques and transcriptome analyses on multiple cell lines and human blood samples to show that trisomy 21 consistently activates the interferon signaling cascade across a variety of cell types…..