Exome sequencing revealed C1Q homozygous mutation in Pediatric Systemic Lupus Erythematosus

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S. Zoghi
V. Ziaee
T. Hirschmugl
R. Jimenez-Heredia
A. Krolo
K. Boztug
N. Rezaei


Pediatric Systemic Lupus Erythematosus, Whole Exome Sequencing, C1Q deficiency


Introduction and objectives: Pediatric Systemic Lupus Erythematosus (pSLE) is an autoimmune disorder of children. Early disease onset raises the probability of genetic etiology and it is more severe than adult SLE.

Patients and methods: Herein an eight-year-old girl with pSLE from consanguineous parents is reported.

Results: Although she was diagnosed as pSLE since the age of two years, Whole Exome Sequencing (WES) revealed a rare stop-gained C>T mutation in C1QA gene. The variant was validated and segregated inpatient and the family. Furthermore, serum levels of the C1q protein were measured and found to be much lower than normal ranges.

Conclusions: This study indicated that C1Q deficiency should be considered as a differential diagnosis of pSLE. Therefore, measurement of C1q should be recommended in all cases with pSLE.

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