Genetic of uveitis.

Immune-mediated uveitis may be associated with a systemic disease or may be localized to the eye. T-cell-dependent immunological events are increasingly being regarded as extremely important in the pathogenesis of uveitis. Several studies have also shown that macrophages are major effectors of tissue damage in uveitis. Uveitis phenotypes can differ substantially, and most uveitis diseases are considered polygenic with complex inheritance patterns. This review attempts to present the current state of knowledge from in vitro and in vivo research on the role of genetics in the development and clinical course of uveitis. A review of the literature in the PubMed, MEDLINE, and Cochrane databases was conducted to identify clinical trials, comparative studies, case series, and case reports describing host genetic factors as well as immune imbalance which contribute to the development of uveitis. The search was limited to primary reports published in English with human subjects from 1990 to the present, yielding 3590 manuscripts. In addition, referenced articles from the initial searches were hand searched to identify additional relevant reports. After title and abstract selection, duplicate elimination, and manual search, 55 papers were selected for analysis and reviewed by the authors for inclusion in this review. Studies have demonstrated associations between various genetic factors and the development and clinical course of intraocular inflammatory conditions. Genes involved included genes expressing interleukins, chemokines, chemokine receptors, and tumor necrosis factor and genes involved in complement system. When considering the genetics of uveitis, common threads can be identified. Genome-wide scans and other genetic methods are becoming increasingly successful in identifying genetic loci and candidate genes in many inflammatory disorders that have a uveitic component. It will be important to test these findings as uveitis-specific genetic factors. Therefore, the burgeoning understanding of the human genome promises to result in new insight into the pathogenesis of uveitis.