SQSTM1 and oculopharyngeal muscular dystrophy: On immunohistochemistry for anti-PABPN1 in OPMD, PABPN1-positive aggregates were observed in the myonuclei, corresponding to the p62 positive myo-INIs (Fig. 1o), while PABPN1-positive aggregates were absent in the myo-INIs of the other diseases.