STIM1 and Thrombocytopenia: Functional investigations in the cellular model have shown that the STIM1 and ORAI1 mutations lead to excessive cytosolic Ca2+ levels through SOCE over-activation [9,11,13,14,15,16,17,18,19], and a recently reported TAM/STRMK mouse model harboring the most common STIM1 mutation p.Arg304Trp (R304W) was shown to exhibit elevated cytosolic Ca2+ levels in skeletal muscle and to recapitulate the main clinical signs of the human disorder including muscle weakness, thrombocytopenia, smaller size, and eye, skin, and spleen anomalies [20].