By Grant Jacobs 21/12/2015

It’s the time for lights, tinsel, and the fragrance of pine indoors.

But growing in the wild those ‘Christmas trees’ are a curse in New Zealand. They’re a weed that overhauls our native species. They take over the landscape. It takes a lot of labour to remove them, even when small.

TV3’s Story recently covered one effort to try eliminate them.

Korean pine seeds. The edible seeds are Korean pine nuts. Source Wikipedia. Attribution: GFDL
Korean pine seeds. The edible seeds are Korean pine nuts. Source: Wikipedia. Attribution: GFDL

The Christmas trees they talk about are Pinus contorta, not the Pinus radiata of forestry, but they’re both weedy pests. A 12 year old, 5m tall Pinus contorta produces 15 000 viable seeds a year.

They’re a conservation and tourism mess.

Bee keepers dislike them, as they want blocks of native forest (partly to meet the regulations to be able to claim specialist types of honey).

Forestry dislikes them, too; they want plantations as they planted them without stray plants.

They can also impact water-limited settings and affect wildfires.

Imagine a future New Zealand where if you wanted to grow pines, you had an option to—or were obliged to—grow non-wilding pines. Pines that were infertile, unable to spread on their own.

It’d mean we wouldn’t be adding to the problem, and might help us get on top of it and eventually nail it for good.

Wilding pines in Canterbury (NZ). Alan Liefting, public domain.
Wilding pines in Canterbury (NZ). Alan Liefting, public domain.

Several years ago, the Environment Protection Agency (EPA) approved New Zealand company Scion to use enzyme-based mutagenesis techniques to develop new tree varieties. Among these were non-wilding pines.

But nearly two years ago a High Court case blocked this, overturning the ruling.

Breeding new varieties using mutagens, processes that introduce variation in the genes of a species is well accepted and usually considered separately from techniques that introduce new genes.

Mutagenesis is any process that introduces variation in the genes. It happens naturally in all species, including in us. We typically have about 30-50 variations (mutations) that are brand new in us, not present in either of our parents.

Things that chemically create new variation are called mutagens.

Mutagenesis does not introduce DNA from other species, one of the main things people opposed to genetically-modified plants object to.

We’ve used mutagens to create new varieties for a long time. Six years ago Parry and colleagues noted,

Over the past 70 years, more than 2500 varieties derived from mutagenesis programmes have been released, as listed in the IAEA/FAO mutant variety database, including 534 rice lines, 205 wheat lines, and 71 maize lines

This database now holds over 3,200 entries.

Among the things that can create variation in DNA sequences (mutations) are several small chemicals. These are accepted under New Zealand law. They’re considered safe ways to breed new varieties.

Pine cone, Istria, Croatia. Petar Milošević, CC4.0. (Source: WIkipedia.)
Pine cone, Istria, Croatia. Petar Milošević, CC4.0. (Source: Wikipedia.)

Basically, they speed up the search for new variants. The mutagens randomly make changes throughout the plant’s DNA, and the breeders select from the plants they get.

Over the past twenty-odd years, scientists have been developing new, improved ways of creating variants, in particular ways that that only affect chosen locations in the DNA.[1]

These are enzyme-based counterparts to the small-molecule mutagens that are accepted under our new organism regulations.

The main difference is that the enzyme-based techniques are designed to change only one location in the plant’s genome, rather than randomly throughout the genome.

This exploits what we’ve learnt about genomes. If we know particular genes are essential for the fertility of a plant’s seeds, for example, we could make one those genes non-functional – and the plant infertile.

You could get something very similar — functionally identical — by screening ‘conventionally’ bred plants, looking for the rare ‘natural’ variations, but you’d need very large trials and be at it for a very long time, especially for slow-growing things like trees.

How did new approaches to a breeding technique that is generally accepted (and does not use genes from other species) get placed under tight regulation?

I’ll spare you the details of the court case,[2] but the ruling left New Zealander effectively ‘banning’ a non-GMO technique that is widely accepted elsewhere (including by countries that accept growing transgeneic plants).

So we can’t try make non-wilding pines by knocking out some of the genes essential for the fertility of the seeds. An over-zealous approach to attacking new techniques from an interest group has seen to that.

So far.

‘Japanese’ red pine, from the North/South Korean border zone. Author: yeowatzup at Flickr; source: Wikimedia.
‘Japanese’ red pine, from the North/South Korean border zone. CC2.0. Author: yeowatzup at Flickr; source: Wikimedia.

The Minister for the Environment, Nick Smith, has recently backed the idea of changing our GMO regulations in response to four options (and variants of these) presented to them by the Ministry for the Environment.

The High Court case revealed a grammatical error in the regulations.[3] This error meant varieties already in use developed under long-established mutagenesis techniques would be placed approval.

The four options were to do nothing, leave the regulations as they are; make limited changes that only address the immediate concerns of the High Court[2]; move forward cautiously; revisit the GMO legislation in the HSNO Act.

The temporary patch recommended by the Minister is to use 29 July 1998 as a ‘magic date’,[4] with mutagenesis techniques in use before this date as “OK” and those after this date held up for approval.

This is unfortunately a double-edged sword. It will “free” the use of new varieties made from old, ‘random’, mutagenesis techniques from the regulation wording stuff-up but in the very same act lock down new varieties developed under newer mutagenesis techniques, even though these are widely accepted as not creating ‘GMOs’ and are recognised as less problematic than the older mutagenesis techniques.

Taken at face value, this magic date approach make us hicks who want to freeze progress in time, extreme technophobes.

There are better options.

It’s fair to suggest that most concern about new breeding techniques is over those that transfer genes from one species to another. [5]

Another approach would be to hold up for approval only those new varieties developed by adding genes from other species.[6]

This is still ‘not there’ in that it falls short of what is needed, but would require reworking the legislation [2,7], but at it’s least moving forward in a way I’d like to think most people accept.

Among other things, with these new mutagenesis breeding techniques we might take a smart approach to tackling those wilding pines. Develop varieties that are non-wilding, pass regulations to ensure that’s all New Zealanders avoid growing varieties that spread, and perhaps in time see the end of the wilding pines.

Wouldn’t that be a treat?


1. These include techniques based on joining a DNA-binding protein  and an DNA-cutting enzyme. One example is is ZFN-1 that was in the High Court case. (These were first developed before the 1998 “deadline” Cabinet proposes to apply to the regulations. They are unlikely to have been used in a field application until later, however.)

2. One problem with all this is that I’m not of the opinion that the High Court ruling is what should have been called. In my opinion the suggested option actually re-enforces the unfortunate outcome of this court case, rather than rectify it.

I’ve written some coverage of the case at the time, see Gene editing and GMOs in NZ, part one; parts two and three are linked in the first paragraph. (There would ideally be a fourth part breaking down the case, but I fear few would read it.)

3. There are two “levels” involved here: the legislation, and the regulations used by the legislation. Option two and three only tackle the latter; option four would (also) tackle the former.

4. This same date is used to define some cases of what a new organism is considered to be, e.g. “An organism that arrived in New Zealand after 29 July 1998.”

This option is a variant of option 2 from the Ministry for the Environment suggestions.

It’s worth noting that the use of an arbitrary date sets up a double standard based on a label (‘GMO’) rather than be based on what cause risk or not (the traits each variety has).

Bear in mind that this is meant to be a temporary position, with later revision. Having said that it’d be wise to ensure we move forward: temporary ‘patches’ with short-comings applied long-term can cause quite a bit of damage.

5. I’m not saying I agree with that view. The issue of why people object to this is interest, and I think stems from cultural memes (not science per se) – something I’d like to tackle another day.

6. Using the ‘technique + genotype’ variant of option 3.

I don’t want to go into details in this post. You could set the genotype criteria to be several things, and these quickly get very complex (which to me only highlights that the regulations and legislation are focused ultimately on the wrong thing). I’m taking my lead of how it could be usefully set in the interim from what I perceive people to have concern with. As I noted in the article this isn’t based on what I believe is best in the long-term (or what accurately reflects risk), but based on what I believe is acceptable to most.

A tidbit: we contain transgenes. So do kumara.

What reflects risk are trait-based approaches. It’s worth noting that the Ministry for the Environment note this themselves in their recommendations. They also note that precautionary approaches are not ‘no risk’ approaches.

7. In the long term the GMO clauses want to be removed from the HSNO Act. A concern expressed by cabinet is the time it would take to correct the immediate issue of the wording of the regulation if something bigger like overhauling the legislation is done. The option I’ve mentioned should be able to be set in place fairly quickly as it’s the current suggestion with a simple restriction to varieties that include genes from other species added.

Some related articles on Code for Life

GMOs and the plants we eat: neither are “natural”

Kumara are transgenic

Gene editing and GMOs in NZ, part one

GMOs and legislation: useful suggestions for New Zealand in British report

Changing the GMO regulations – the ministry options

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