Textbook of Personalized Medicine - Second Edition [2015]

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Lab 21 says they’ll keep all genetic information private, and their Web site claims
the genetic samples are destroyed immediately after the analysis is complete.
GeneLink Inc invented the fi rst genetically designed patentable DNA test for cus-
tomized skin care products, and in partnership with DNAPrint, is screening millions
of candidate biomarkers. Tests are designed to assess genetic risks for certain skin
disorders due to nutritional defi ciencies and provide a basis for recommending for-
mulations that have been specifi cally designed to compensate for these defi ciencies.


Management of Hair Loss Based on Genetic Testing


Androgenetic alopecia occurs with increasing phenotypic expression based on
advancing age, approximately 65 % men and 50 % of women will be affected by the
age of 60. Clinical diagnosis relies largely on the development of a hair loss pattern,
and visible areas of thinning or baldness, which is not apparent until approximately
50 % of hair are lost in a given area. Thus patients will have substantial hair loss
prior to initiation of therapy. However, the two FDA-approved medications to com-
bat hair loss, minoxidil and fi nasteride, are most effective at stabilizing hair loss
rather than hair regrowth. Therefore, a screening test for androgenetic alopecia
which identifi es patients at higher risk for developing it can offer the opportunity for
early medical intervention prior to visible signs of hair loss.
An association between male pattern baldness and the androgen receptor gene
has been confi rmed (Levy-Nissenbaum et al. 2005 ). HairDX ( http://www.hairdx.com )
provides genetic tests for both male and female androgenetic alopecia, which are
administered in the privacy of a physician’s offi ce using a simple cheek swab.
HairDX (RxR) genetic test for fi nasteride response provides men with a score − CAG
repeat score. Smaller CAG test score is associated with an increased response to
fi nasteride for treatment of androgenetic alopecia in men. Among men that had the
best response to fi nasteride approximately 70 % had a CAG score below 22 while
among men that had a subtle response to fi nasteride approximately 70 % had a CAG
score above 22. This test helps to personalize treatment of androgenetic alopecia.


Personalized Preventive Medicine


Genomics and genetics are vital for the development of preventive medicine.
Current practice of preventive healthcare involves general advice applicable to pop-
ulation at large, e.g. dietary measures to lower cholesterol. Integration of new
genetic information into epidemiologic studies can help clarify causal relations
between both life-style and genetic factors and risks of disease. An example is pre-
vention of atherosclerosis where multiple factors interplay in the etiology. Since
atherosclerosis involves arterial infl ammation, a polymorphism in the 5- lipoxygenase
gene promoter could relate to atherosclerosis in humans and that this effect
could interact with the dietary intake of competing 5-lipoxygenase substrates.


18 Personalized Approaches to Miscellaneous Problems in Healthcare
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