Carrier frequency and incidence estimation of deficiency of adenosine deaminase 2 in the Chinese population based on massive exome sequencing data

Deficiency of adenosine deaminase 2 (DADA2) is an autosomal recessive autoinflammatory disease characterised by early onset stroke, recurrent fever, and diverse vascular pathologies, caused by loss-of-function homozygous or compound heterozygous variants of ADA2. This research aimed to determine the carrier frequency and expected incidence of DADA2 in China, using massive exome sequencing (ES) data. A total of 50 likely pathogenic/pathogenic variants (LP/PVs) were identified among 69,413 Chinese individuals, including 20 novel and rare variants (<0.0022 % allele frequency), expanding the known spectrum of PVs in ADA2. The overall carrier frequency in the Chinese population was 1.05 % (732/69,413) and the estimated incidence of DADA2 was approximately one in 92,251 individuals. The present study provides an accurate estimation of the prevalence of DADA2 in China, supporting genetic counseling, early diagnosis treatment, and prognostic evaluation.