The University of Pittsburgh says it is unlikely that its formal investigation into allegations of scientific misconduct by professor Gerald Schatten will be concluded by this month.

The American university was originally scheduled to wrap up investigations around this week, but apparently decided to extend the probe after including in the scope of investigations a thesis on a cloned dog written jointly by Schatten and his former collaborator Hwang Woo-suk.

Meanwhile, the university’s Medical Center spokeswoman, Jane Duffield, said Schatten received a series of questions from a Seoul National University investigative panel on Hwang’s cloning scandal but that such questions have yet to be answered since Schatten is on vacation.

Earlier on Tuesday, the panel said it may question Schatten and Hwang's ex-assistant Park Jong-hyuk by video conferencing on Hwang's stem cell scandal.