Setting research priorities for arthritis: the environmental perspective

Journal article

2005 Jan 01

Journal of Rheumatology Supplement

72

58-61

15660471

No

Recent enthusiasm for genetic advances in prevention is out of keeping with the etiology of most common diseases of the industrialized world, including the major inflammatory arthritides. These conditions have a genetically 'complex' causation, involving many genes, and strong influences of the environment, acting on our individual genetic endowments over the entire life course. Lines of evidence that this is so are reviewed--especially migrant epidemiological cohort studies, which are stronger etiological evidence that 'twins reared apart' studies, since they tend to involve massive cultural and environmental changes, while 'holding genetic factors constant.' More such studies would better inform preventive strategies for the inflammatory arthritides, which lag behind cardiovascular disease in understanding causation, and therefore primary prevention. Finally, factors are briefly reviewed that affect risks, benefits, and costs of single-locus genetic tests to predict lifelong risk of chronic diseases with complex and multifactorial determination. Both negative and positive predictive values of such tests for predicting lifetime disease occurrence are generally unacceptable for use in the general population. Expert genetic counseling is therefore important before such testing, to ensure that an appropriate family and personal history justifies these expensive tests, the 'labeling' effects of which can last a lifetime