@Override
  public boolean equals(Object other){
      if (other == null) return false;
      if (other == this) return true;
      if (!(other instanceof GeneMention))return false;
      GeneMention gm = (GeneMention) other;
      return gm.getId().equals(this.getId()) &&
              gm.getStart() == this.getStart() &&
              gm.getEnd() == this.getEnd();
  }