Estimated prevalence (probability) of genetic susceptibility in rheumatoid arthritis, ankylosing spondylitis, and systemic lupus erythematosus

‡The prevalence of diseases {P(D)} is from data provided in Reference [35].*Studies [36]-[38] report pair-wise MZ-twin concordance-rates. These have been converted into proband-wise rates {P(D|MZD)} assuming a random sampling of twin-pairs [30]. Also, the IU environment has been assumed to have no impact on the disease. A violation of either of these assumptions will make the estimate of P(G) too low.