AMERICAN SOCIETY OF HUMAN GENETICS (ASHG)
THE 11 th ANNUAL DNA DAY ESSAY CONTEST
Cerebrotendinous xanthomatosis (CTX) is a late
onset condition that is related to the abnormal
storage of the lipids inside the body. The cause
of the disease is in an anomaly of a specific gene
– CYP27A1 gene – which also leads to anomalies
on enzyme, named sterol 27-hydroxylase that is
responsible for lipid conversion (Federico & Dotti,
What is CTX - Information about Cerebrotendinous
Xanthomatosis, n.a.). For instance, cholesterol is
converted into one of the bile acids, chenodeoxylic
acid. Due to the failure in this gene, extra cholesterol
is accumulated especially around nerve cells and
tendon, which is the connective tissues of the body
(Cerebrotendinous Xanthomatosis, 2014). Although
biological alcohols are chemically converted into
bile acids, the concentration of bile acids is not
adequate (Christie, 2013).
These changes of body naturally bring up some
symptoms that get even more severe in further
stages of Cerebrotendinous xanthomatosis. Lipid
accumulation on nerve cells lead to dementia, ataxia,
and decrease on mental abilities. In addition to this,
tendon flexibility and movement ability decrease.
Most of the Cerebrotendinous xanthomatosis
patients have cataract, chronic diarrheas and fragile
bone structure (Cerebrtendinous Xanthomatosis
(CTX), n.p).
This is the main reason that the early diagnosis of
the Cerebrotendinous xanthomatosis is fatal in such
consideration. If Cerebrotendinous xanthomatosis
is diagnosed earlier and the treatment might begin
before any critical harm on nervous system is
done, effects can be less harsh and disturbing for
the patient (Federico, Late onset neurometabolic
diseases, 2013).
Before any medical care is taken, doctors do some
testing on family inheritance, health history of
the patient. There are urine and blood sample
tests that are available for further information on
the relation of the person with Cerebrotendinous
xanthomatosis. If any suspicions are still present, the
doctor may recommend a gene testing to examine
the gene structure of the autosomal chromosomes
to see whether the CYP27A1 gene is mutated or
not. This stage helps to get a legitimate result. The
last choice is not highly common in current time,
but there are very recognizable evaluations with
the new projects, such as Human Genome Project
completed in 2003. Mapping of human genome
helps to compare the gene structure of the patient to
the normal gene and detect any mutations on early
stages (Federico & Dotti, What is CTX - Information
about Cerebrotendinous Xanthomatosis, n.a.).
The test available is mostly gas chromatography
mass spectrometry. Plasma sample of the patient
is heated in specially designed machines until
the sample evaporates. The separations of the
molecules in gas state is easier. The concentrations
of some specific substances such as; lipids, bile acids
and alcohols are detected easily (Cerebrotendinous
Xanthomatosis, 2014).
Cerebrotendinous xanthomatosis can be treated by
a serum treatment. The serum mostly contains the
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