Finding causative genes underlying rheumatic disease: could NCF1 pave the way?

Area of Science:

• Genetics
• Immunology
• Rheumatology

Background:

• Identifying genetic risk factors is crucial for understanding rheumatic disease pathogenesis.
• While susceptibility loci are known, causal variants are rarely identified.
• Experimental animal models are valuable for confirming human genetic findings.

Purpose of the Study:

• To identify and validate a causative genetic variant for rheumatic diseases.
• To investigate the role of this variant in disease susceptibility and severity.
• To explore the functional impact and environmental interactions of the identified variant.

Main Methods:

• Positional cloning in animal models followed by exon sequencing.
• Targeted resequencing and linkage disequilibrium mapping in human cohorts.
• Mechanistic studies to explore functional impact and environmental interactions.

Main Results:

• Identified a causative single-nucleotide polymorphism (SNP) in the NCF1 gene (rs201802280).
• This NCF1 variant is a major susceptibility factor for systemic lupus erythematosus, rheumatoid arthritis, Sjögren's disease, and systemic sclerosis.
• The variant influences disease severity and has implications beyond rheumatic diseases, including cancer and cardiovascular conditions.

Conclusions:

• The NCF1 polymorphism is the first major causal variant linked to susceptibility and severity across multiple rheumatic diseases in humans and animal models.
• Viral infections interact with this variant to contribute to lupus pathogenesis in animal studies.
• The NCF1 variant's significance extends to various non-rheumatic conditions, highlighting its broad biological impact.