Science still the key to our future

JON MORGAN

Scientists by nature are cautious. The thoroughness of their methods teaches them that. Even when they arrive at a tried, tested and peer-reviewed result they are reluctant to speak in absolutes.

The word "breakthrough" is anathema to them. They would rather run naked across a Rugby World Cup pitch than use it.

So it was with some surprise that I saw "breakthrough" in the tag line of an email from the Crown science institute, AgResearch.

Delving into this news release, however, was like wading through treacle. Here's an example: "scientists simply incubated skin cells in plasmid DNA encoding the pluripotency factors and watched the cells reprogramme back into an embryonic stem cell-like state".

I was none the wiser, so I rang the scientist quoted, Bjorn Oback.

He stood by the breakthrough tag. And very patiently did his best to explain it to me.

I admit to being as thick as the average journalist, so it wasn't that easy for him, but in the end we got there. What emerged was a stunningly significant discovery.

If taken to its logical conclusion, of which Oback was confident, it will be of immense importance to cattle breeding, particularly dairying, and hence the national economy and the standard of living of all of us.

It will mean breeders won't have to wait six or seven years to see if desirable genes are passed on in succeeding generations: a result can be guaranteed within 12 months.

This breeding process shortcut has repercussions for many lines of research, from the search for cows that give more milk to those that belch less methane.

And also important for New Zealand's international image is that it does not involve genetic engineering.

It should be stressed that what Oback and his team have achieved is just a first step.

It involves making a special type of stem cell.

But first, a primer on stem cells. Mammals are made up of many specialised cell types. Normally, they are stable and do not switch jobs - blood cells do not turn into brain.

Stem cells are an exception. They are "on standby", locked into a dormant, yet responsive state. When tissues need repair, the appropriate stem cells are activated and replace the damaged cells, demonstrating their enormous flexibility.

The most flexible of all stem cells are pluripotent ones, which can generate all cell types. It is these cells that Oback's team have developed.

They have grown them in a medium that has chemical inhibiters to stop them from changing into the other specialist stem cells.

What makes this research different is that it avoids the ethical dilemmas that come with other methods of creating stem cells, which involve the destruction of embryos or the viral insertion of DNA.

Oback wants to move the research out of the lab and take pluripotent cells from a cattle embryo with a special attribute - milk or meat production, disease resistance, fertility, whatever is desired. They would then be inserted into another embryo, developed into a calf and grown to a young bull.

What is wanted is the bull's sperm. The pluripotent cells that make the sperm are the guarantee that those attributes will be passed on.

It saves having to wait for two or more generations to come from that bull to be sure. The cells can then be taken from the sperm and put into many embryos.

That lies ahead for Oback's team.

So far, after four years' work, they have proved that pluripotent bovine stem cells will develop into different tissues in mice. Next, they want to do it in cattle.

An indication of the strong likelihood of their success is that a major sponsor is the dairy and beef genetics company CRV AmBreed.

The publication of this work, in the prestigious online scientific journal PLoS ONE, comes at a time when scientists are being made redundant because of government budget cuts.

Some months ago, I argued for making agriculture the centre of a national strategy that looks many years ahead. Science is a crucial part of that. We should be finding a way to retain these people, and looking at how their skills can fit into the agriculture research wish- list.

I know we have a big earthquake debt, but this genetic breakthrough shows that spending more money on scientists, not less, makes sense.

- © Fairfax NZ News