PENISES grown in laboratories could soon be ready for human testing after “encouraging” studies on rabbits, in a breakthrough for men with congenital abnormalities or traumatic injuries.

Researchers at North Carolina’s Wake Forest Institute for Regenerative Medicine are assessing engineered penises for safety, function and durability, and hope to get approval for human testing within five years.

The organ would be grown using a patient’s own cells to minimise the risk of rejection.

Professor Anthony Atala oversaw the institute’s successful engineering of penises for rabbits in 2008 and said human organ transplantation was on the horizon.

“The rabbit studies were very encouraging but to get approval for humans we need all the safety and quality assurance data, we need to show that the materials aren’t toxic, and we have to spell out the manufacturing process, step by step,” he said, according to The Guardian.

The newspaper reports it would take about four to six weeks for cells from the patient’s penis to grow in a culture.

Scientists start the process by washing a donor penis in a mild detergent to remove all donor cells. About two weeks later when just a collagen scaffold of the penis is left, scientists “seed” the patient’s cultured cells.

The pioneering work is funded by the US Armed Forces Institute of Regenerative Medicine, which hopes to use the technology to help soldiers injured in service.

However Professor Atala says it would also benefit men with congenital abnormalities.

Right now, men can have their penis reconstructed using forearm or thigh flesh. A penile prosthetic is implanted to simulate an erection.