... loss -of- function of BTK and ITK and the gain -of- function fusions ITK–SYK and BTK–SYKAlamdar Hussain1,2,*, Liang Yu1,3,*, Rani Faryal1,2, Dara K. Mohammad1, Abdalla J. Mohamed1,4 and C. I. ... missing data.The phenotype of XLA and thepotential of BTK and ITK inhibitorsThe outcome of defective BTK signaling in humanshas been described previously in detail [26,27], and therefore we will ... with XLA, and theeffects of these mutations have been analyzed in alarge number of in vitro and in vivo studies [45]. About20 mutations affect residues directly involved in ligand binding, ...