CONTENTS
Before We Begin . . . 1
An introduction
1 It’s Who You Are 9
You need to understand some basic terms and ideas to make sense of
the DNA sciences. Don’t know a gene from a chromosome? This is the
place to start.
2 How We Got Here 27
Fifty years after Watson and Crick discovered the DNA double helix, the
Human Genome Project announced the final version of the human
genome. How did we get here from there? Here’s an inside look at how
one of the biggest discoveries in the history of mankind came about.
3 Your Genome—An Owner’s Manual 55
You are of the first generation in the history of the human race to
understand what makes you . . . well, you. The fascinating discoveries
scientists have made about DNA could change your life, your health,
and society.
4 The DNA Files 69
The most important advance to come out of his work, says DNA double
helix discoverer James Watson, is the exoneration of death row
inmates. DNA fingerprinting has revolutionized crime solving, and is
helping historians solve centuries-old mysteries.
5 Fa incg Destiny 87
It would’ve seemed like science fiction just a few decades ago, but
today genetic testing can predict susceptibility for hundreds of disorders.
Who are the innovators? What tests are out there? Will government
permit insurance companies and employers to discriminate
using the new knowledge? Genetic testing, in plain English.
6 The Fountain of Aging Well 113
It is one of DNA science’s most exciting fields. Biogerontology. A San
Francisco scientist has increased a worm’s lifespan sixfold! Two
gerontologists are betting a half-billion dollars that in 2150, at least
one person alive today will still be alive! Meanwhile, companies vie to
create a pill that will help tomorrow’s baby-boomer senior citizens
seem decades younger than their years.
7 Closing in on Cancer 133
In the 1970s, Nixon declared war on cancer. This was back when doctors
thought it was a single disease. By the mid-1990s, most scientists
had lost hope, and cancer deaths were at an all-time high. Now, for the
first time, the majority of cancer specialists have renewed faith that,
thanks to the DNA sciences, most cancers will be cured—in the next
twenty years. Here are the players and the technologies.
8 Cloning and Stem Cells 157
It doesn’t get more controversial than this. Despite calls for a global ban
on cloning—both the kind that produces “mini me” humans and the kind
that yields potentially life-saving stem cells—the world’s scientific community
is pushing hard to keep stem cell work alive, saying it’s our best
hope of curing most of the degenerative diseases that kill people today.
Here is an inside look at the players, and the arguments from both sides.
9 Gene Therapy 173
Gene therapy—or actually modifying defective genes in patients to
cure them—was once the holy grail of DNA medicine. Then came setbacks—
a teenager dies in a gene therapy trial and several French children
get leukemia—and everything changed. Now gene therapy
experts are trying to fight their way back to the forefront with a long
list of therapies and cutting-edge trials in labs around the country.
VI ~ CONTENTS
10 DNA and Society 193
When most people hear the word eugenics, they think of the Nazis’
attempt in the 1930s and 1940s to murder their way to an Aryan
Germany. But few people know that eugenics—the pseudoscience of
genetically breeding humans—was first popularized decades earlier in
America. Eugenics was the first societal effort to manipulate genetics.
Should we fear that a new eugenics is in the offing? What are the
ethical issues as the DNA sciences barrel into the future?
Notes 211
Glossary 225
Every word you’ll ever need to know to keep up with DNA researchers
and companies in the news, for investing and making societal and personal
choices.
Index 255
IT IS A GREATER achievement than the discovery of vaccines
and antibiotics combined. And it is no exaggeration to say that, as a
result of it, the world of human beings will never be the same.
I am talking, of course, about the discovery of the DNA double
helix by an American and a Brit, James Watson and Francis Crick,
in 1953. On a chilly February day, something profound happened.
It barely got a mention in the papers that whole year. But Watson
and Crick, they knew. “We found it!” Crick shouted upon bursting
into The Eagle, an off-campus pub close to their University of
Cambridge lab. “We have found the secret of life!”1
In April 2003, fully fifty years later, history was made again. A
group of scientists announced they had taken Watson and Crick’s
great insight to yet another level. They published an enormous
list—a list of the chemicals that make up all the genes in the DNA
BEFORE WE BEGIN. . .
I N T R O D U C T I O N
of the human race. In other words, they published the sequence of
the human genome. And now the life-changing work can begin.
Knowing what a human being is made of is the first step toward
knowing how to fix that human being when something goes wrong,
or how to prevent something from going wrong in the first place.
Eventually, it might even mean knowing how to build a better
human being altogether. All of this is important, critical, even. But
something also happened when this knowledge came to light. We
humans—who are so happy with ourselves and our ability to reason,
to investigate, to manipulate nature—became the first beings
on the planet to take a look at ourselves at the most primary level,
discovering the language in which our very existence is written.
The sum total of genes in a species—the DNA information that
determines whether you have hair or hooves, teeth or a tail—is
called the genome. Genomics is the emerging science of understanding
the human genome, and of determining how the DNA in
every human being affects identity, health, and disease. And
genomics is launching other sciences almost as quickly as you can
learn the terms. First functional genomics, then comparative
genomics, then proteomics . . . the science breaks into subsets and
into subsets again.
But one thing is certain. No matter how you slice and dice it, the
new science of DNA will transform everything it touches: Medical
treatment and diagnosis, especially. Criminology and genetic profiling.
Cancer research and anti-aging. History. Ethics. Politics. And
don’t forget about the economy. Universities and businesses are
sinking tens of billions of dollars into DNA-related fields.
“It’s a giant resource that will change mankind, like the printing
press,” says James Watson, who should know.2
Johannes Gutenberg invented the movable-type printing press
around 1450, and by the year 1500, there were a thousand books in
Europe. That pace of change is generally considered to be extraordinary,
but this DNA revolution puts that progress to shame.
2 ~ THE GENOMICS AGE
In 1985, when I was an undergraduate studying chemistry at
Florida State University, my organic chemistry professor told the
class that the human genome wouldn’t be mapped in our lifetimes.
For a while, it looked like he was right. After all, the first genome—
of the simple bacterium that causes meningitis—wasn’t even
decoded until 1995. It was tiny, and even that took years to do.
Then science turned a corner. Thanks mainly to advances in
computer technology, researchers were able to outline the first draft
of all three billion components of human DNA, about 200 New
York City phone books worth of As, Cs, Ts, and Gs.
There still is an enormous amount of work to be done.
Researchers are now trying to understand the contents of the book
they have opened. According to Francis Collins, Human Genome
Project leader, it is as if we have discovered the Book of Life, only
to find the book is written in an unknown language. That means
there is much left to do, and the benefits of the DNA sciences will
arrive piecemeal, as we become increasingly fluent in its grammar
and peculiar turns of speech.
And we must be careful not to get carried away with the hype
surrounding this high-profile work. The tendency, says Collins, is
to hear about the discovery of a new gene—such as a gene related
to diabetes or heart disease—and immediately expect a cure for
the ailment.
“Predictions in science tend to be over-optimistic in the short
run,” Collins told me as I was finishing up the first draft of this
book. “But they tend to be under-optimistic in the long run. I think
that applies here, too. Wildly overstated expectations of immediate
benefits and [disease cures] from the Human Genome Project
helped fuel the biotech frenzy of the late 1990s, but no one I knew
thought that these expectations had any chance of happening at
such a rapid pace.
“When the investment bubble burst,” he added, “some people
began to complain that the Human Genome Project was a failure
BEFORE WE BEGIN ~ 3
and hadn’t paid off. But it was the outrageous predictions that failed
and didn’t pay off. We will get there. It will happen. But not tomorrow
or the next day. After all, it’s one thing to derive the three billion
letters of the code accurately and publicly. We’ve done that. But
it will now require the best and brightest brains on the planet to go
to the next level of understanding.”3
But anyone wanting to put their excitement on hold because of
that long to-do list need only look at extremely important genomics
work that has already arrived. These results would’ve seemed like
science fiction just a few years ago.
Consider. DNA evidence testing has proved the innocence of
144 convicted inmates—and counting—as of this writing.4 It’s
cleared so many people on death row that, in 2003, then-governor
George Ryan of Illinois commuted all the state’s death sentences to
prison terms of life or less.
Even historical crime mysteries are finding solutions. For
instance, DNA evidence seems to have posthumously vindicated
Sam Sheppard, who was accused of killing his wife in 1954. (You
may remember the Sheppard case as the inspiration for the TV
show and movie, The Fugitive.) The long-standing rumor that
Thomas Jefferson fathered children with his slave, Sally Hemings,
is now confirmed. Genetic tests show that some of the Hemings
children were directly related to a Jefferson male.
And DNA evidence is being used to figure out everything from
where Christopher Columbus is buried to whether Billy the Kid
actually died in the1880s or, as rumored, lived on to be known as
Brushy Bill, the elderly nursing home resident who, in the 1950s,
claimed to be him.
The field of genetic testing is currently exploding, too. As
researchers peg more and more gene mutations to specific disorders,
DNA tests allowing you to be tested for them are right
behind. You and your unborn child can already be tested for susceptibility
for hundreds of diseases. In some case, finding out
4 ~ THE GENOMICS AGE
about a potential disorder and taking measures now to avoid it can
save your life.
DNA medications are starting off more slowly, but they’re coming,
too. The startling effectiveness of DNA medicines such as
Enbrel for rheumatoid arthritis and Gleevec for a certain kind of
leukemia paints an optimistic future for medicines that precisely target
the genetic problem behind a disease. And scientists believe they
are on the threshold of creating personalized medicines—chemicals
specially designed to work best with your particular genetic makeup.
The holy grail of the DNA sciences—the immediate tracing of
every human disease and disorder to a single gene or group of
genes—is further off. Yes, there has been progress in finding the
genes linked to diseases such as cancer, heart disease, and diabetes.
You’ll read about a lot of that progress in this book. But it is certain
to be more difficult than people once suspected. Most disorders
aren’t just mutations of a single gene, but many. And to treat
genetic diseases, it will be necessary not only to understand the
gene involved, but also the proteins the gene makes and everything
that happens along the pathway from mutation to disorder. This
will be the hard part.
Yet whether it takes years or decades, this much is certain:
Medicine is forever changed. Because scientists now understand
something about DNA, they are already using DNA knowledge to
manufacture human hormones, help reduce heart blockages, shrink
tumors, and treat multiple sclerosis. More developments are coming
and, if history is any guide, they will greet us at a faster and
faster rate.
Eventually, we will be living in a world where diseases are not
just treated; they will be prevented from occurring in the first place.
Nobel Laureate David Baltimore told me that he had chills when
he first read the paper that detailed the human genome. And he’s
seen a lot of biology in his long career. He is now the president of
the California Institute of Technology.
BEFORE WE BEGIN ~ 5
Biology, he says, has entered a new era. “Instead of guessing
about how we differ one from another, we will understand and be
able to tailor our life experiences to our inheritance. We will also
be able, to some extent, to control that inheritance. We are creating
a world in which it will be imperative for each individual person
to have sufficient scientific literacy to understand the new riches
of knowledge, so that we can apply them wisely.”5
Scientists such as Baltimore have long understood the frontier
of the human genome and what it means to human beings. For the
rest of us, it’s taken a little longer. For most Americans, the science
and terminology of the DNA revolution are brand new, just now
appearing in the papers and on TV.
The science of DNA is simple, elegant, and ultimately graspable.
You just need a little background in it, a little insight into who’s
doing what, what’s coming, and what’s just plain hype.
Cutting to the quick of the so-called DNA revolution is what this
book is all about.
✸ ✸ ✸
My goal with this book is to stick to developments likely to
unfold in the next several years, detailing the advances that DNA
research is expected to bring. That way, you can profit from the
knowledge in your lifetime.
In the first three chapters, I’ll get you familiar with the terms,
techniques, and background you need to understand the rising tide
of DNA stories in the news. If you don’t know a gene from a chromosome—
or if you just need a refresher on some newer terms and
techniques—this section is for you.
Then, we’ll take a look inside the labs, where key developments
are happening in the hot areas of DNA fingerprinting, gene testing,
cancer research, gene therapy, cloning and stem cell research,
and anti-aging experimentation. In Chapters 4 through 9, you’ll
6 ~ THE GENOMICS AGE
meet the minds behind the science, plus gain a plain English understanding
of how they’re taking on the challenge.
Finally, we’ll reflect. Though I’ve included comments from ethicists
and social scientists throughout, Chapter 10 digs deeper into
the ethical issues facing us all. Should governments be permitted to
compile DNA databases of each and every one of us? Could genetic
testing result in an uninsurable and unemployable underclass? How
will the DNA revolution affect your life and that of your family? I’ll
examine how current developments and their rush to reality will
change the world for our children and our children’s children.
These are issues we all need to think about. But without a decent
grounding in the science of DNA—who the players are and what
the technology is all about—the right decisions are difficult to
make. You can’t invest in or follow the DNA industry without knowing
this stuff, either.
It’s my hope that this book will give you not only the insight into
what’s happening in this historic revolution, but also the lay language
and background to ask the hard questions—of yourself, the
politicians who represent you, the business world, and the scientific
community. There aren’t too many other books that take on this
challenge, but you’ve found one.
Now, onward!
BEFORE WE BEGIN ~ 7
No comments:
Post a Comment