Transgenic Goats

SHEILA McGOVERN
Southam Newspapers

Reproduced by permission of the Calgary Herald

SAINT-TELESPHORE, Que.

They look like unlikely lifesavers. Adorable baby dwarf goats - like the ones you see in a petting zoo. Nubian goats with big floppy ears, sticking their heads out of their pens and staring inquisitively at the humans in white overalls who have entered their barn.

But Nexia Biotechnologies Inc. expects those goats will be able to produce life-saving human proteins - quickly and in quantity - in their milk within about a year.

Then Nexia and its partner, Genzyme Transgenic Corp. of Framingham, Mass., will spend the next several years developing medications from those proteins. Pharmaceuticals are a fiercely competitive industry, and Jeffrey Turner, Nexia's president, can't be too specific about what exactly it is they are after, Nexia itself is pursuing a growth hormone that would, among other thing, bolster immune systems of transplant recipients and reduce the side-effects of chemotherapy. Genzyme is looking for a blood product, Turner said, and "...that's all I'm allowed to tell you."

The goats made their public debut this week as Nexia, a four-year-old biotech company located in Ste. Anne de Bellevue, Quebec, officially opened its transgenic farm - one of only three such farms in the world, Turner said. The others are Genzyme's farm near Boston and PPL Therapeutics in Scotland, which garnered worldwide headlines last winter when it produced Dolly the sheep, the first cloned mammal.

Turner quickly points out that cloning and genetic engineering at that level raise many unanswered ethical questions, and that is not the type of research Nexia is pursuing. However, PPL also produced another sheep named Tracy, he said, and she and her four daughters have the capacity to fill the world's needs for a particular clotting agent. That is the type of research Nexia is pursuing.

To bring the research down to a layman's level, Turner explained that many diseases stem from a defective gene that prevent a person from creating specific proteins. Diabetics, for example, lack the ability to produce insulin and hemophiliacs lack the proteins that make blood clot. There are drugs on the market that provide many of these proteins, he said, but they are drawn from human blood - a major and costly undertaking that also carries a risk of viruses being transmitted to the recipient.

So Nexia is engineering its goats to produce the proteins. An embryo is extracted and a single highly characterized human gene is inserted. The embryo is then put back into the mother or a surrogate mother, who will, hopefully, produce a transgenic offspring. It works 5 to 10 per cent of the time. The goats that are not transgenic are kept for breeding.

A transgenic goat carries about 55,000 goat genes and one human gene, Turner said, "It's still a goat." But a female transgenic will carry within her mammary gland the gene to produce human protein in her milk, he said, adding that it took years of research to come up with a way to program the gene to go into the mammary gland.

To speed up the process, Nexia has developed its own type of dwarf goat known as the BELE Ä-which stands for breed early, lactate early. The goat matures more rapidly and is sexually active year round.

They can produce milk at 12 months instead of 18. They are not allowed contact with other animals to prevent the passing of any diseases. One of the toughest tasks in establishing the farm, which was pulled together in four months, was finding a location where no other animals had been kept. Nexia finally selected an old sugar bush near the Ontario border. The site is surrounded by a fence - to keep other animals away - and humans visiting the goats must dress in special overalls and boots to prevent their passing on any of their germs. "Besides keeping them healthy, you have to keep them happy," he said, so Nexia provides devices for them to walk up and down and climb on, and toys - they like soccer balls. Of course, more militant animal rights activists won't be satisfied, he said, because the goats are kept in pens. Nexia has come a long way fairly fast. Turner spent eight years at McGill University, before deciding to give up his tenure and head for the private sector in September 1993. Nexia has received about 8.5 million in investment from MDS Health Ventures Inc., Societe Innovatech de Grand Montreal, Sofinov (a subsidiary of the Caisse de Depot et Placement du Quebec) and the Canadian Medical Discoveries Fund, he said, and Genzyme is contributing 2.5 million. It has 25 employees, who are young and enthusiastic, Turner said.

"I'm the old man and I'm 38." Like many fledgling biotech companies, it isn't making any money - it just keeps putting money into research and development, but doesn't yet have a product to sell. However, he is optimistic the company will start making money next year and hopes to list on the stock market within a year or two.

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