CENTER FOR CANCER AND BLOOD DISORDERS
TREE OF LIFE
HOW DOCTORS USED GENEALOGY TO CATCH COLE CHAVEZ’S
DEADLY DISEASE
Meet Cole
Grandmother
(April)
Aunt
(Ashley)
Mother
(Shannon)
Cole
Cousin
(Ethan)
It started, for Cole Chavez’s cousin Devan, with trouble in
school. Teachers thought he just wasn’t paying attention. When
a hearing test came back normal, it soon became clear there
was more to it. A neurologist ordered an MRI.
Uncle
(Bryson)
Sister
Sister Brother
(Hannah) (Kaelie) (Austin)
Cousin
(Devan)
Cousin
(Izabelle)
KEY:
non-carrier
Cole was diagnosed
and prepared for a
transplant before
he ever showed
symptoms.
male carrier
female carrier
Knowing the disease’s
heritability, doctors at
Children’s Colorado
immediately began
tracing the disease up
the family tree, identifying
Cole and Devan’s
grandmother as the point
of origin. They tested
everyone. Devan’s mother,
Ashley, unknowingly had
the disease. So did Shannon.
And so did Cole, her
youngest son.
“By the time we met him, he’d been
showing symptoms for over a year,”
says Ralph Quinones, M.D., a pediatric
bone marrow transplant physician at
Children’s Hospital Colorado. “He was
late in the disease.”
The news was devastating: Devan
had x-linked adrenoleukodystrophy
(X-ALD), a genetic disease that
produces abnormal lipids, or fats,
the molecular building blocks
for many hormones — leading
to lifelong gland and hormone
problems. Far more troubling is its
effect on the brain.
Lipids also make up the myelin
sheaths around nerve cells, and
the irregular lipids of X-ALD
provoke an inflammatory response:
recognizing something amiss, the
immune system attacks the myelin,
destroying neurons’ protective
coating and causing massive
cerebral damage. Young boys,
after three or four years of normal
development, begin a sudden, rapid,
and eventually fatal regression as the
nervous system deteriorates. That’s
what was happening to Devan.
“It took his vision, his hearing,
his ability to eat, walk, to use the
restroom,” says Shannon Chavez,
Cole’s mother and Devan’s aunt,
who is herself a carrier of X-ALD.
Because the disease is linked to
the X-chromosome, its carriers
are women, whose additional
X-chromosome tends to mitigate
the disease’s effects. In boys,
however, it has lethal consequences.
Timing is crucial with X-ALD.
Done early enough, a bone marrow
transplant can correct the immune
response, halting damage to the
brain before it begins. Cole was
diagnosed and prepared for a
transplant before he ever showed
symptoms. His bone marrow came
from an anonymous donor, a nearly
100-percent genetic match, who
was understandably reluctant
at first to go through with the
excruciatingly painful process of
donating his bone marrow. “But
when they told him it was for a
6-year-old boy and he was going
to die without it,” says Shannon,
“he did it.”
It worked. Cole is now 7 years old
and making full use of his recent
discovery of sarcasm — his deadpan
is withering, and his practical jokes
are legendary around the Center for
Cancer and Blood Disorders. The
Chavez family recently celebrated
his first “rebirthday,” so called
“because when he had his transplant,
he got new genetics,” Shannon says.
Without a doubt, the bone marrow
transplant saved his life.
“If it hadn’t been for Devan,” Dr.
Quinones says, “we never would
have caught it in Cole.”
Devan, too, had a bone marrow
transplant, but his disease had
progressed too far. His system
rejected new bone marrow, causing
a massive inflammation that took
his sight. A second bone marrow
transplant, doctors thought, would
compound that result.
“He was 7 years old when he died,”
Shannon says. “It’s hard for me even
now: I have my son and it’s because
of my nephew. And he knew it. He
was very proud of that in the end.”
Cole Chavez and sister Kaelie, both carriers
of X-ALD, working hard on Cole's puff-paint
snowflake (it turned out great).
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