Systemic lupus erythematosus: a genetic epidemiology study of 695 patients from China

Abstract

Our purpose was to explore potential genetic models for systemic lupus erythematosus (SLE) and analyze genetic epidemiologic characteristics of SLE in a Chinese population. Data for 695 patients with SLE were obtained by using a uniform questionnaire. Patients, clinical characteristics and their family history were analyzed using software. A complex segregation analysis was conducted to propose potential genetic models for SLE. The mean +/- SD age of onset were 30.2 +/- 10.5 years and mean time to progression to SLE was 32.5 +/- 44.4 months. The most frequent initial manifestations were malar rash (61.3%). During the evolution of the disease, the main clinical features were arthritis in 73.6% of our patients, followed by malar rash (68.1%), and renal involvement (56.7%). As the first symptom, the late-onset group (onset of disease beyond the age of 50 years) less often showed malar rash (45% vs. 63.4% in the early-onset group; p = 0.001). There were no significant differences in the other cumulative clinical symptoms between late-onset and early-onset group, except for a lower prevalence of malar rash, photosensitivity and alopecia and a higher prevalence of mucosal ulcers in the late-onset group. A positive family history of SLE was obtained in 50 patients (7.2%). There were no statistical differences in clinical characteristics between familial SLE and sporadic SLE patients. The heritability of SLE was 43.6%, the genetic model of SLE could be polygenetic model and major gene mode is the best fitted one. SLE could be a multifactorial disease with polygenetic model.

Early disease onset is predicted by a higher genetic risk for lupus and is associated with a more severe phenotype in lupus patients

“…This finding opposes that of Wang et al 22 in a study of 695 Chinese patients with SLE where they observed photosensitivity in 16.3% of late-onset and 29.3% of early-onset SLE cases. These differences are probably due to race, as our population has <2% Asian composition.…”

Genome-wide association study of skin complex diseases

“…SLE is a prototypic systemic autoimmune disease characterized by autoantibody production, complement activation, and tissue and organ damage [30] and influenced by both genetic and environmental factors [31]. Severity, risk and clinical manifestation of SLE were varied by race, geography and sex [32][33][34][35].…”

A mega-analysis of genome-wide association studies for major depressive disorder

“…13 For example, there have been notable successes in genome-wide searches 14 for susceptibility loci for breast cancer (heritability ~25%), lung cancer (26%), Type 2 diabetes mellitus (26%), Parkinson’s disease (34%), multiple sclerosis (41%), systemic lupus erythematosus (44%) and age-related macular degeneration (46%). 15–20 …”