JERUSALEM, Sept. 10 (Xinhua) – Israeli scientists have developed a method that allows unprecedented observation of embryonic stem cell differentiation, the Weizmann Institute of Science (WIS) reported Tuesday.

The study, published in the journal Molecular Cell, is another step in solving one of the great mysteries of life – a tiny ball of identical cells implants itself in the uterus, and somehow, these cells begin to differentiate – each heading for a different fate.

Every cell in the human body contains the same genome, but the epigenetics – changes on top of the genome that regulate the cell's activities – differ from cell to cell.

Epigenetic changes are especially crucial during prenatal development, since at any given time, numerous genes must be temporarily turned on while others are kept silent.

The WIS researchers have combined several advanced techniques to develop a method for tracking epigenetic activity in real time, with single-cell resolution.

“For years we have had ‘reporters’ – DNA encoding glow-in-the-dark proteins – that can track gene expression,” the researchers said. “But until now, we haven't had the same tools for epigenetics”.

The new technique is essentially a reporter that can be inserted into the genome to reveal its epigenetics, so these changes can be observed – even minute ones – within single living cell.

“We can now begin to put together the rather elaborate mechanics of the cell's decisions in the very first days and weeks of embryonic development, to understand how the potential of an embryonic stem cell is eventually narrowed down to a particular cell fate,” the researchers concluded.