In a pioneering research involving stem cells, researchers in the US have successfully used a cloning technique to make insulin-producing cells with the DNA of a diabetic woman.

A team led by regenerative medicine specialist Dieter Egli at the New York Stem Cell Foundation Research Institute derived embryonic stem cells from a cloned embryo containing the DNA from a 32-year-old woman with type 1 diabetes.

The researchers also succeeded in differentiating these ES cells into insulin-producing cells - opening a new pathway for treating diabetes by replacing pancreatic cells.

"The new work is a step toward providing genetically matched replacement cells for transplant," Egli said.

To produce the cloned embryos, the researchers used an optimised version of the laboratory technique called somatic-cell nuclear transfer (SCNT).

In the technology, the nucleus from a patient's cell is placed into an unfertilised human egg which has been stripped of its own nucleus.

This reprogrammes the cell into an embryonic state.

SCNT was the technique used to create the first mammal cloned from an adult cell - Dolly the sheep - in 1996.

The eggs were grown into early embryos.

From these, the scientists removed stem cells, which can grow into any cell type in the body.

The scientists turned these stem cells into the insulin-producing cells.

According to researchers, the breakthrough is a step toward providing perfectly genetically matched replacement cells for transplant.

In a previous research this month, researchers led by Young Gie Chung and Dong Ryul Lee at the CHA University in Seoul reported in Cell Stem Cell that they had cloned embryonic stem-cell (ES cell) lines made using nuclei from two healthy men, aged 35 and 752.

The studies show that the technique works for adult cells and in multiple labs, marking a major step.

"It's important for several reasons," said Robin Lovell-Badge, a stem-cell biologist at the MRC National Institute for Medical Research in London.

The research has been published in the journal Nature.