Genetic research sheds light on children’s arthritis

There is new hope for treating a type of arthritis that commonly affects children, thanks to ground-breaking genetic research out of Waipapa Taumata Rau, University of Auckland’s Liggins Institute.

World-wide, three million children and young adults are estimated to suffer from juvenile idiopathic arthritis, a type of joint disease that occurs when the body's immune system attacks its own tissues.

However, the exact causes of juvenile idiopathic arthritis remain unknown. Scientists have identified many genetic factors that may be important, but still do not understand the biological mechanisms that contribute to juvenile idiopathic arthritis.

A new paper by Liggins Institute researchers shows that genetic changes in 51 regions of the human genome alter the expression of 210 genes that are important for juvenile idiopathic arthritis. See the open-access Journal of Autoimmunity.

Juvenile idiopathic arthritis is known as a joint disease, but other parts of the body can also affect joint health.

“Interestingly, many of the changes in gene regulation occurred in tissues that are not classically considered central to juvenile idiopathic arthritis pathology, such as muscle, blood vessel, fat, and even the brain,” says lead author and doctoral student Nicholas Pudjihartono.

Consistent with the autoimmune features of juvenile idiopathic arthritis, the “target genes were involved in immune-related pathways such as antigen processing and presentation, release of pro-inflammatory cytokines, proliferation of specific immune cell types, and pathological joint inflammation,” says Professor O’Sullivan.

“These results are important, as the genetic changes that affect gene regulation in multiple tissues may contribute to juvenile idiopathic arthritis risk by increasing inflammation throughout the body.

“At the same time, changes to gene regulation in specific tissues and/or cell types can help us understand how different parts of the body contribute to juvenile idiopathic arthritis and its complications.”

This game-changing research highlights the complex genetic factors that contribute to juvenile idiopathic arthritis.

Future work needs to focus on the exact roles of these genes in the disease process, and how they might interact with other conditions that co-occur with juvenile idiopathic arthritis.

This information can help in developing better treatments for juvenile idiopathic arthritis and by extension other autoimmune conditions.

·       Read Juvenile idiopathic arthritis-associated genetic loci exhibit spatially constrained gene regulatory effects across multiple tissues and immune cell types