DNASE1L1 encodes a deoxyribonuclease structurally related to DNase I, located on chromosome X. The protein exhibits nuclease activity and contains a predicted signal sequence, transmembrane domain, and helix-loop-helix motif 1. In vertebrate evolution, DNASE1L1 acquired a glycosylphosphatidylinositol anchor for plasma membrane attachment in bony fishes, facilitating its role in extracellular DNA degradation alongside other DNase family members 2. The gene is expressed at high levels in skeletal and cardiac muscle with lower expression in other tissues 1. DNASE1L1 appears in alternative splicing signatures associated with uveal melanoma prognosis, where exon-skipping events influence patient overall survival 3. At the population level, genetic variation in DNASE1L1 is limited; population-level SNP analysis reveals that synonymous polymorphisms show minimal frequency variation across ethnic groups, with one non-synonymous variant restricted to Caucasian populations 4. Expression quantitative trait loci mapping has identified SNPs in DNASE1L1 associated with variation in bilirubin levels, type 1 diabetes risk, and schizophrenia 5. While no disease-causing mutations were detected in Barth syndrome or Emery-Dreifuss muscular dystrophy patients in early studies 1, amplifications of DNASE1L1 on Xq28 have been identified in all nine mature cystic teratomas examined, suggesting a potential role in teratoma formation 6.