Email: djawaheer@chori.org
Phone: 510-450-5664

CHORI Staff Directory
CHORI Intranet
CHORI News

 

Overview

The research in the laboratory of Damini Jawaheer, PhD, is focused mainly on the genetics and epidemiology of Rheumatoid Arthritis (RA), with a goal of providing a better understanding of the risk factors involved in the susceptibility and severity of this disease.

RA is a chronic systemic inflammatory disease with autoimmune features that affects approximately 1% of the adult world population, and results in synovial joints being attacked by one's own immune system. RA is one of the leading causes of chronic impairment worldwide, contributing largely to the global burden of disease. This is reflected in the designation of 2000-2010 as the Bone and Joint Decade by the United Nations, World Health Organization, and more than 60 countries around the world. Over the last two decades, there have been some major advances in the treatment of RA. New disease-modifying anti-rheumatic drugs (DMARDs), including biologic agents, such as anti-TNF therapy, have shown a high degree of efficacy in management of the disease and in controlling its progression. Nonetheless, there is no cure for the disease.

The etiology of RA is as yet unknown. It is clear, however, that the disease is multifactorial, likely resulting from complex interactions between genes and environmental factors. A genetic component to RA susceptibility has long been established by data from twin and family studies. A twin analysis estimated the heritability of RA to be 60% [1]. The strength of the genetic component has also been estimated by computing the value of "lambda s", i.e. the relative recurrence risk for siblings of RA probands compared with that for the general population, which has been estimated to be in the range from 2 to 17 [2]. A consistent association between RA and human leukocyte antigen (HLA)–linked genes has been observed in many populations [3]. Although much evidence points to a role for HLA-DRB1 alleles, the exact identity of the HLA susceptibility genes has not been established with certainty, and there is some evidence that other genes within the HLA complex may also be associated. The exact mechanisms underlying the HLA associations with RA are, however, still unknown. It has been estimated that genes within the HLA region may account for 1/3 to 1/2 of the genetic component in RA [4]. Thus, the balance of the evidence indicates that genes outside the HLA region may account for 1/2 to 2/3 of the genetic component in RA. With the emergence of genome-wide association studies (GWAS), associations with several non-HLA loci have now been reported and confirmed in independent studies. No causal variants have as yet been identified.

References:

  1. MacGregor AJ, Snieder H, Rigby AS, Koskenvuo M, Kaprio J, Aho K, et al. Characterizing the quantitative genetic contribution to rheumatoid arthritis using data from twins. Arthritis Rheum. 2000 Jan;43(1):30-7.
  2. Seldin MF, Amos CI, Ward R, Gregersen PK. The genetics revolution and the assault on rheumatoid arthritis. Arthritis Rheum. 1999;42(6):1071-9.
  3. Ollier W, Thomson W. Population genetics of rheumatoid arthritis. Rheum Dis Clin North Am. 1992;18(4):741-59.
  4. Deighton CM, Walker DJ, Griffiths ID, Roberts DF. The contribution of HLA to rheumatoid arthritis. Clin Genet. 1989;36(3):178-82.

 

© 2005 Children's Hospital Oakland Research Institute
5700 Martin Luther King Jr Way • Oakland, California 94609
Phone 510-450-7600 • Fax 510-450-7910
Site MapDisclaimer