A deep dive into monogenic lupus: insights on DNASE1L3 mutation

Area of Science:

• Genetics
• Rheumatology
• Immunology

Background:

• Monogenic lupus is a rare autoimmune disease caused by specific genetic mutations.
• DNASE1L3 mutations are implicated in a subset of lupus cases, particularly in childhood-onset systemic lupus erythematosus (cSLE).
• Understanding the phenotype and outcomes of DNASE1L3-related lupus is crucial for diagnosis and management.

Purpose of the Study:

• To describe the largest cohort of monogenic lupus attributed to DNASE1L3 mutations.
• To characterize the phenotypic features and clinical outcomes of affected individuals.
• To compare the characteristics of DNASE1L3-related lupus with sporadic cSLE.

Main Methods:

• A multicenter retrospective chart review was conducted.
• Patients with genetically confirmed homozygous DNASE1L3 mutations and childhood-onset systemic lupus erythematosus (cSLE) were included.
• Data from the monogenic lupus cohort were compared with a cohort of sporadic cSLE patients.

Main Results:

• 33 patients from 15 families with homozygous DNASE1L3 mutations were identified.
• Disease onset was typically early (median 4 years), with a higher proportion of affected boys (61%).
• Common symptoms included arthritis (82%), urticarial vasculitis (79%), nephritis (60%), and pulmonary hemorrhage (15%), with many cases refractory to standard treatment.

Conclusions:

• cSLE caused by DNASE1L3 mutations exhibits early onset, aggressive disease course, and treatment resistance.
• Further research into targeted therapies to restore or compensate for DNASE1L3 function is necessary.
• This study highlights the importance of genetic testing in diagnosing and managing severe childhood-onset lupus.