该基因编码一种参与v（d）j重组和dna修复的核蛋白。该编码蛋白具有单链特异性的5'-3'外切酶活性，在5'和3'的外突和发夹上也表现出内切酶活性。这种蛋白质还可以调节细胞周期，以应对dna损伤。该基因突变可导致阿萨巴扫描型严重联合免疫缺陷（scida）和大网膜综合征。选择性剪接导致多个转录变体[由RefSeq提供，2014年1月]
This gene encodes a nuclear protein that is involved in V(D)J recombination and DNA repair. The encoded protein has single-strand-specific 5'-3' exonuclease activity; it also exhibits endonuclease activity on 5' and 3' overhangs and hairpins. The protein also functions in the regulation of the cell cycle in response to DNA damage. Mutations in this gene can cause Athabascan-type severe combined immunodeficiency (SCIDA) and Omenn syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]