[tt] NYT Letters: Getting to Know Your DNA

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Getting to Know Your DNA
http://www.nytimes.com/2007/11/23/opinion/l23dna.html
[Target article added, which I sent earlier.]

To the Editor:

Re My Genome, Myself: Seeking Clues in DNA (The DNA Age series,
front page, Nov. 17):

Wanting to know more about ourselves is both a strength and a
hazard. The lure of genetic data can be compelling but misleading,
for no list of tiny variants in ones genetic code can reliably
predict ones future regarding cancer, heart attacks or diabetes,
let alone I.Q., addiction or gullibility.

Amy Harmons humorous account of her own genome search may still
leave many readers willing to send off a little saliva and a big
check to a genome company. Those companies are selling only a
fragment of your identity. Knowing that you have this or that
disease-associated SNP in your genes tells you very little or helps
only with rare diseases.

What causes the SNP (single nucleotide polymorphism) to be
expressed, to spring into action or to remain dormant? Why can
identical twins, with genomes alike down to the last SNP, develop
different diseases? What if you smoke, toil for years in a
high-stress job or live in a polluted neighborhood?

Predispositions are just the beginning. Your future depends on much
more than your genetic code. Ms. Harmon would have done better to
spend her money on a good gym, and The Times would serve us better
by emphasizing the limits of genetic knowledge.

Susan M. Reverby, Ph.D.
Jay Kaufman, Ph.D.
H. Jack Geiger, M.D.
Cambridge, Mass., Nov. 18, 2007

Dr. Reverby is professor of the history of ideas at Wellesley
College; Dr. Kaufman is associate professor of epidemiology at the
University of North Carolina, Chapel Hill; and Dr. Geiger is
emeritus professor of community medicine at City University of New
York Medical School.

To the Editor:

The exposé on surfing for ones genome demonstrates the slipperiness
of tapping genetic information. Personally, Id rather not know
about my predilection for certain tastes mainly because it would
take the fun out of trying new foods. (Not the cream of lobster: Im
lactose-intolerant and lack the taste gene for bottom-feeding sea
creatures!!)

Yet I recognize the importance of genetic research in biology and
medicine. The paradox is that to make intellectual strides, society
must accept some risk. People should recognize that a wealth of
both critical and inconsequential genetic information is becoming
available. But within privacy laws, they should also be able to
keep the right to choose the movies they watch, the Web sites they
frequent and how much they want to learn about their genetic
potential.

Andrew Zinn, M.D.
Kew Gardens, Queens, Nov. 17, 2007

To the Editor:

Amy Harmon mentions the risk that insurers might deny coverage
based on future availability of a persons detailed genetic
information. The future also poses a risk that employers could
misuse genetic screening and data.

Since 1990, most states have passed laws to prevent genetic
discrimination, but federal protection is essential. The Genetic
Information Nondiscrimination Act of 2007 was passed by the House
this spring; Senator Olympia Snowe, Republican of Maine, has
proposed a Senate version. If you are worried about such
discrimination (and you should be), contact your senators to voice
your support of this legislation.

Katherine Brokaw
Atlanta, Nov. 17, 2007

To the Editor:

The real news is that the genetic genie is out of the bottle. The
consumers embrace of genetic analysis is now unstoppable. And
though the medical community warns how little we can actually learn
from most of our genes, these caveats do not diminish our
curiosity.

The truth is that the medical establishment has not co-opted the
genetic paradigm because doctors are busy and see little value
right now for themselves or their patients. As such, genetics may
go the way of cosmetic dermatology and surgery.

Hugh Young Rienhoff Jr., M.D.
San Francisco, Nov. 18, 2007

The writer is director of http://MyDaughtersDNA.org., a forum on 
genetics.


My Genome, Myself: Seeking Clues in DNA
http://www.nytimes.com/2007/11/17/us/17dna.html

The DNA Age
My Genome, Myself: Seeking Clues in DNA
By AMY HARMON

The exploration of the human genome has long been relegated to
elite scientists in research laboratories. But that is about to
change. An infant industry is capitalizing on the plunging cost of
genetic testing technology to offer any individual unprecedented
and unmediated entree to their own DNA.

For as little as $1,000 and a saliva sample, customers will be able
to learn what is known so far about how the billions of bits in
their biological code shape who they are. Three companies have
already announced plans to market such services, one yesterday.

Offered the chance to be among the early testers, I agreed, but not
without reservations. What if I learned I was likely to die young?
Or that I might have passed on a rogue gene to my daughter? And
more pragmatically, what if an insurance company or an employer
used such information against me in the future?

But three weeks later, I was already somewhat addicted to the daily
communion with my genes. (Recurring note to self: was this
addiction genetic?)

For example, my hands hurt the other day. So naturally, I checked
my DNA.

Was this the first sign that I had inherited the arthritis that
gnarled my paternal grandmothers hard-working fingers? Logging onto
my account at 23andMe, the start-up company that is now my genetic
custodian, I typed my search into the Genome Explorer and hit
return. I was, in essence, Googling my own DNA.

I had spent hours every day doing just that as new studies linking
bits of DNA to diseases and aspects of appearance, temperament and
behavior came out on an almost daily basis. At times, surfing my
genome induced the same shock of recognition that comes when
accidentally catching a glimpse of oneself in the mirror.

I had refused to drink milk growing up. Now, it turns out my DNA is
devoid of the mutation that eases the digestion of milk after
infancy, which became common in Europeans after the domestication
of cows.

But it could also make me question my presumptions about myself.
Apparently I lack the predisposition for good verbal memory,
although I had always prided myself on my ability to recall
quotations. Should I be recording more of my interviews? No, I
decided; I remember what people say. DNA is not definitive.

I dont like brussels sprouts. Who knew it was genetic? But I have
the snippet of DNA that gives me the ability to taste a compound
that makes many vegetables taste bitter. I differ from people who
are blind to bitter taste who actually like brussels sprouts by a
single spelling change in our four-letter genetic alphabet:
somewhere on human chromosome 7, I have a G where they have a C.

It is one of roughly 10 million tiny differences, known as single
nucleotide polymorphisms, or SNPs (pronounced snips) scattered
across the 23 pairs of human chromosomes from which 23andMe takes
its name. The company generated a list of my genotypes ACs, CCs,
CTs and so forth, based on which versions of every SNP I have on my
collection of chromosome pairs.

For instance, I tragically lack the predisposition to eat fatty
foods and not gain weight. But people who, like me, are GG at the
SNP known to geneticists as rs3751812 are 6.3 pounds lighter, on
average, than the AAs. Thanks, rs3751812!

And if an early finding is to be believed, my GG at rs6602024 mean
that I am an additional 10 pounds lighter than those whose genetic
Boggle served up a different spelling. Good news, except that now I
have only my slothful ways to blame for my inability to fit into my
old jeans.

And although there is great controversy about the role that genes
play in shaping intelligence, it was hard to resist looking up the
SNPs that have been linked however tenuously to I.Q. Three went in
my favor, three against. But I found hope in a study that appeared
last week describing a SNP strongly linked with an increase in the
I.Q. of breast-fed babies.

Babies with the CC or CG form of the SNP apparently benefit from a
fatty acid found only in breast milk, while those with the GG form
do not. My CC genotype meant that I had been eligible for the
6-point I.Q. boost when my mother breast-fed me. And because, by
the laws of genetics, my daughter had to have inherited one of my
Cs, she, too, would see the benefit of my having nursed her. Now
where did I put those preschool applications?

I was not always so comfortable in my own genome. Before I spit
into the vial, I called several major insurance companies to see if
I was hurting my chances of getting coverage. They said no, but
that is now, when almost no one has such information about their
genetic make-up. In five years, if companies like 23andMe are at
all successful, many more people presumably would. And isnt an
individuals relative risk of disease precisely what insurance
companies want to know?

Last month, alone in a room at 23andMes headquarters in Mountain
View, Calif., with my password for the first time, I wavered
(genetic?) and walked down the hall to get lunch.

Once I looked at my results, I could never turn back. I had
prepared for the worst of what I could learn this day. But what if
something even worse came along tomorrow?

Some health care providers argue that the public is unprepared for
such information and that it is irresponsible to provide it without
an expert to help put it in context. And at times, as I worked up
the courage to check on my risks of breast cancer and Alzheimers, I
could see their point.

One of the companies that plans to market personal DNA information,
Navigenics, intends to provide a phone consultation with a genetic
counselor along with the results. Its service would cost $2,500 and
would initially provide data on 20 health conditions.

DeCODE Genetics and 23andMe will offer referrals. Although what
they can tell you is limited right now, all three companies are
hoping that people will be drawn by the prospect of instant updates
on what is expected to be a flood of new findings.

I knew I would never be able to pass up the chance to fill in more
pieces of my genetic puzzle.

But I had decided not to submit my daughters DNA for testing at
least not yet because I didnt want to regard anything about her as
predestined. If she wants to play the piano, who cares if she lacks
perfect pitch? If she wants to run the 100-meter dash, who cares if
she lacks the sprinting gene? And did I really want to know did she
really want to know someday what genes she got from which parent
and which grandparent?

I, however, am not age 3. Whatever was lurking in my genes had been
there my entire life. Not looking would be like rejecting some
fundamental part of myself.

Compelled to know (genetic?), I breezed through the warning screens
on the site. There would be no definitive information, I read, and
new discoveries might reverse whatever I was told. Even if I
learned that my risk for developing a disease was high, there might
well be nothing to do about it, and, besides, I should not regard
this as a medical diagnosis. If, after considering these points,
you still wish to view your results, the screen read, click here.

I clicked.

Like other testers of 23andMes service, my first impulse was to
look up the bits of genetic code associated with the diseases that
scare me the most.

But in the bar charts that showed good genes in green and bad ones
in red, I found a perverse sense of accomplishment. My risk of
breast cancer was no higher than average, as was my chance of
developing Alzheimers. I was 23 percent less likely to get Type 2
diabetes than most people. And my chance of being paralyzed by
multiple sclerosis, almost nil. I was three times more likely than
the average person to get Crohns disease, but my odds were still
less than one in a hundred.

I was in remarkably good genetic health, and I hadnt even been to
the gym in months!

Still, just studying my DNA had made me more acutely aware of the
basic health risks we all face. I renounced my midafternoon M&Ms.

And then I opened my Gene Journal for heart disease to find that I
was 23 percent more likely than average to have a heart attack.
Healthy lifestyle choices play a major role in preventing the
blockages that lead to heart attacks, it informed me.

Thanks, Gene Journal. Yet somehow even this banal advice resonated
when the warning came from my own DNA.

Back in New York, I headed to the gym despite a looming story
deadline and my daughters still-unfinished preschool applications.
At least I had more time. I had discovered a SNP that likely
increased my life span.

But in what I have come to accept as the genomic law of averages, I
soon found that I might well be sight impaired during those extra
years. According to the five SNPs for macular degeneration I fed
into the Genome Explorer, I was nearly 100 times more likely to
develop the disease than someone with the most favorable A-C-G-T
combination.

And unlike the standard eat-right-and-exercise advice for heart
health, there was not much I could do about it. Still, I found the
knowledge of my potential future strangely comforting, even when it
was not one I would wish for. At least my prospects for nimble
fingers in old age were looking brighter. I didnt have the bad form
of that arthritis SNP.

Maybe I was just typing too much.