RESUMEN
<p><b>OBJECTIVE</b>Interleukin 7 (IL-7) and its receptor（IL-7R）are essential for normal T-cell development and homeostasis. This study was aimed to investigate the IL-7R mutation and its clinical significance in adult patients with adult acute lymphoblastic leukemia (ALL), particularly in T-ALL.</p><p><b>METHODS</b>The exons of IL-7R were amplified, cloned and sequenced in 144 adult patients with ALL; the frequency, position and lypes of IL-7R mutation were detected and their correlation with clinical features was analyzed.</p><p><b>RESULTS</b>7.3% of T-ALL and 1.1% of B-ALL showed somatic IL-7R mutations which located at exon 6 and exon 5, respectively. Moreover, the IL-7R mutation was associated with poor clinical outcome in adult ALL patients. Furthermore, the co-existence of IL-7R mutation with NOTCH1 mutations and/or PHF6 mutation in T-ALL was observed.</p><p><b>CONCLUSION</b>IL-7R mulation and its associated signaling pathways may play an important role in the pathogenesis of T-ALL.</p>