G3BP1 and Alstrom syndrome: •Simultaneous expression of ERVK and TDP-43 is one of the hallmarks of ALS.•An increase in expression of G3BP1 was seen in ALSs vs. controls. This may be due to the increased expression of TDP-43 seen in ERVK+ cortical neurons.•No colocalization was observed between G3BP1 and ERVK.•SGs and viroplasms segregation can be a trigger to increased expression of ERVK viral proteins in ALS.