الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
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Pharmacogenetics concerns itself with a special
type of inborn error of metabolism, the response of
individual to drugs.,The aberrant response may be manifested
only in a need for a dose di fferent from that
usually given to achieve a desired theraputic effect
or may be responsible for marked deviations from normal
that may have mild, moderate, or serious untoward
effects, including death.
A number of mendel ian disorders habe been identified
and are discussed.
One of the most informative loci in the human ~p.ne~.
tics is the X-linked gene determining the red blood
cell enzyme glucose-6-phosphate dehydrogenase., Over
90 mutant alleles are known, many of which determine
enzyme deficiencies, resulting in a haemolytic response
to more than 20 drugs,as. well as infection.
It is likely that further genetic differences influencing
responses to drugs will be foun d, thus pe rmt t t ,
ing increasing accuracy in determining doses, choosing
appropriate drugs, and avoi ding undesirable side reaction.
For example, of a man prepared to do an surgical
operation under general anaesthesia with a family hi~-
tory of a death under unaesthesia is least likely to
develop succinyl apnoea due to paralysis of striated
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muscle which may be prolonged and the patient may stop
voluntary breathing for an hour or more.
Also this patient may develop malignant hyperthermia
which may be fatal.
Another example is the hypersensitivity. involving
a defective enzyme wh ich cause s a borderline Ieve lr o r
act ivj tY wit h b0 r der lin e sy m ptom s 0 fen zy me de f ic ien cy
when the adminstered chemical is the primary toxic agent.
Example of this condition involve the primaquine-”
induced haemolytic anaemia in which there is a genetic~
ally altered stability of reduced ’glu!a~~hione and an
altered glucos-6-phosphate dehydrogenase activity.
Additional examples are the abnormal haemoglobins
in which there is an altered ability of the haemoglobin
to remain in the reduced state. and the sulfonamide and
barbiturate-induced porphyrias which are involved with
the deficiency of the inhibitor system which normally
controls the level ofa(-amino livulinic acid synthetase.
Th~ example~’ given here. besides domenstrating the’
truth of the adage that one me n ’s medicine is another
man1s poison. remained us that our genes make us unique
pharmacelogially. as in so many other ways. the pharma-
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cogenetic differences may make it desirable to screen
high risk families and high risk populations before
exposing them to certain agents and that patients being
treated with drugs should be regarded as individuals,
not just as so many kilograms uf body mass.