CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 10, November 2012
AFRICA
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substantial majority of our young patients is with myocardial
infarction, which carries a worse prognosis than stable CAD,
further contributes to adverse long-term outcomes. Indications
are that revascularisation procedures are not as efficacious in
this population.
The availability of quantitative polymerase chain reaction,
which is a simpler, less labour-intensive and cheaper method
requiring smaller quantities of DNA compared to the standard
method of southern blot analysis, has made it feasible for us to
determine telomere length in our patients.
124,125
The study of telomere dynamics may serve several functions.
Firstly, measuring telomere length in the early years of life may
indicate a genetic predisposition and help target susceptible
individuals. Studies on the genetic contribution to premature
CAD with genome-wide association scans have yielded little
thus far, whereas an assessment of telomere length provides a
more universal insight into the genetics of CAD.
Secondly, telomere length is a measure of cumulative DNA
damage from multiple environmental risk factors over an
individual’s lifespan and is likely a better predictor of CAD
than the currently available risk markers, which are single, point
measurements in time.
Thirdly, although the development and progression of
atherosclerosis occurs over decades, the process is clinically
silent until the manifestation of full-blown disease. The rate of
telomere shortening is accelerated prior to the onset of clinical
disease, so longitudinal assessments of telomere length may be
of predictive value. Finally, novel therapies aimed at delaying
cellular senescence by manipulation of the telomere/telomerase
complex may be of benefit.
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