By Eleanor Bradford BBC Scotland health correspondent

Edinburgh is said to be ahead of other hospitals

As National Transplant Week draws to a close, BBC Scotland has learned that Edinburgh is ahead of other units in its bid to carry out the procedure.

The final hurdle is believed to be ethical concerns over the procedure.

Experts have said the operation carries a significant risk for both the donor and recipient.

At the moment livers are only taken from donors who are classed as brain stem dead, but last year alone 15 people died waiting for a liver to become available.

Doctors say it is possible to carry out a transplant from a living donor by taking half the liver.

It is the only organ in the human body that has the ability to regenerate once it is implanted and so it re-grows in both the donor and the recipient.

Risk factor

Live liver transplants involving children have taken place in the UK. This procedure does not carry as high a risk as the recipient needs a smaller part of the donor organ.

The procedure has been used on adults in the United States, but it carries a significant risk to both parties.

About one in 200 patients will die.

Edinburgh is the first transplant unit to be granted permission from transplant authorities to perform the operation in the UK.

Now it says it needs permission from the Scottish Executive to move forward.

At the moment that is being held up on ethical and financial grounds, but with the organ shortage growing, this is an option experts say the NHS will have to give serious consideration.