MUSK and myasthenia gravis: Rapsyn-clustered AChR currents, by contrast, were inhibited by 6/11 AChR-Ab positive sera and by 0/10 AChR-Ab negative MG sera (p=0.0020, Fisher’s exact test, table 1), and the mean current inhibition by AChR-Ab positive sera was significantly higher than the other MG or HC sera (8.0%±1.9% in HC sera, 9.8%±0.8% in MuSK-Ab positive sera, 9.4%±2.1% in SNMG sera and 19.1%±3.4% in AChR-Ab positive sera, p=0.0385, one-way ANOVA; figure 3E).