Christopher Helman, Forbes Global
In
a concrete bunker on a mothballed Air Force base in Plattsburgh, New York, two
Nigerian dwarf goats named Mille and Muscade joyfully munch grass and slurp water.
Oddly, they are protected from intruders by security guards and razor wire.
Only
20 weeks old, these sister beasts warrant tight security because their milk is
highly prized by the U.S. military. Their 70,000-gene chromosomes have been manipulated
to include a gene from the orb weaver, a palm-size spider that spins the world's
toughest natural material. Researchers are "growing" the spider's silk inside
Mille and Muscade's mammary glands.
These
strands of silk, just 3 microns thick, are three times as tough as DuPont's bulletproof
Kevlar. A woven cable as thick as your thumb can bear the weight of a jumbo jet.
Once perfected, the silk will be used for featherweight ballistic vests, medical
sutures and artificial ligaments.
The goats represent a promising new avenue
in the controversial field of transgenics, the science of splicing one species'
genes onto the genome of another. Most efforts, including the recent news of a
disease-detecting rhesus monkey (bred with a glowing jellyfish gene), focus on
improving the characteristics of existing organisms.
But Jeffrey Turner,
the molecular geneticist behind the goat gambit and CEO of the publicly held Nexia
Biotechnologies, has more pragmatic goals. He believes that his animals can mass-produce
drugs and highly engineered materials more cheaply and efficiently than vats and
machines. Rivals include the Pharming Group of the Netherlands, Genzyme Transgenics
in Boston, Massachusetts, and PPL Therapeutics of Scotland.
Nexia is tackling
a materials-science conundrum that has stumped even DuPont for 20 years: how to
synthesize spider silk. Milking the spiders themselves is out of the questionÑthey're
cannibals. "Put a bunch of them together and soon you end up with one big, fat,
happy spider. It's like trying to farm tigers," says Turner. By
injecting the orb weaver gene into the father of Mille and Muscade, Nexia bred
she-goats whose mammary glands are able to produce the complex proteins that make
up spider silk. Their milk looks and tastes like the real thing, but once its
proteins are filtered and purified into a fine white powder, they can be spun
into tough thread.
Turner got the idea while teaching at McGill University
in Montreal in 1992, after learning that scientists had isolated three spider
genes that code for silk proteins. "It was a purely serendipitous find. The silk
gland of spiders and the milk gland of goats are almost identical. Teats equal
spinnerets."
In 1993 he founded Nexia with $2 million in venture capital.
He started with mouse embryos and graduated to goats, whose large mammary glands
make better milk machines. The Nige-rian dwarf goat was the perfect candidate,
as it begins breeding and lactating at just 13 weeks. In 1998Nexia flew 130 goats
from New Zealand to its facilities on the Plattsburgh base, so that the herd could
quickly expand.
Commercial spider silk is two years away, but Nexia's recent
public offering raised $27 million, enough to cushion losses that ran $3million
last year on $320,000 in revenue. Turner's goats may run dry if the spider silk
hits it big. His expansion plan? Spidercows. |
