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ORIGINAL ARTICLE
Genetic Polymorphism of Drug-Metabolizing Enzymes
CYP2C9 and CYP2C19 in Moroccan Population
Driss Afilal,
1
Mohamed Amine Basselam,
1
Zahra Brakez,
1
Said Chouham,
1
Anto´ nio Brehm,
2
and El Hassan Izaabel
1
Background: The polymorphic cytochrome P450 isoenzymes CYP2C9 and CYP2C19 are involved in the
biotransformation of a wide variety of clinical drugs. Their major alleles occur with varying frequencies among
different populations worldwide and have been associated with a varied capacity to degrade important thera-
peutic agents. This gives rise to important individual and interethnic variability in the metabolism and may be
the cause for different clinical responses regarding drug administration. In this study we aimed to analyze the
distribution of the CYP2C9 and CYP2C19 major alleles associated with the impaired metabolism, and that
account for the ‘‘poor metabolizer’’ phenotype in our study population.
Methods: A sample of 290 healthy subjects living in South Morocco was genotyped using a restriction fragment
length polymorphism-polymerase chain reaction genotyping method.
Results: The CYP2C9*3 and CYP2C19*3 mutations were not found in our population. The CYP2C9*2 and
CYP2C19*2 were the most common alleles, respectively with frequencies of 8% and 11.4%. Regarding CYP2C9*2
and CYP2C19*2, approximately 16% and 22% of Moroccans are respectively deficient metabolizers, and thus
largely lack this enzymatic activity. Our results suggest that only CYP2C9*2 and CYP2C19*2 are likely to sub-
stantially contribute to individual and interethnic variability of CY2C9-19 activity in our population.
Conclusions: The distribution of clinically relevant alleles of the CYP2C19 and CYP2C9 genes among our
population follows the patterns commonly found in other Mediterranean populations, and suggests a certain
degree of African influence. This population study provides relevant information on polymorphisms within the
CYP2C19 and CYP2C9 genes. In the future, these results could be used in prognosis and for predicting response
to drug treatments as well as to help develop personalized medicine studies in the Moroccan population.
Keywords: CYP2C9 and CYP2C19 genes, South Moroccan population, poor metabolizer (PM) phenotype, drug
metabolism, individual and interethnic variability
Introduction
The cytochrome P450 (CYP450) superfamily of hemo-
proteins are the principal enzymes involved in human
drug metabolism and bioactivation. Genetic variation in cy-
tochrome genes plays an important role in differences to
medication response and toxicity. A number of functional
polymorphisms affecting expression or resulting in protein
with variable levels of activity have been identified in genes
belonging to this superfamily (Ingelman-Sundberg, 2004;
Boz
ˇina et al., 2009; Zanger and Schwab, 2013).
The human CYP2C is an important subfamily of cyto-
chrome P450 enzymes that metabolizes a wide variety of
drugs. Members of this subfamily, CYP2C18, CYP2C19,
CYP2C9, and CY2C8, are encoded by a cluster of polymorphic
genes tandemly located on chromosome 10q24 (Goldstein and
de Morais, 1994; Gray et al., 1995; Klose et al., 1999; Gold-
stein, 2001). The best known members CYP2C9 and CYP2C19
genes have received particular attention in recent years because
they are involved in the metabolism of 20% of human drugs
and are the major determinants of their systemic clearance and
their bioavailability (Rosemary and Adithan, 2007; Pinto and
Dolan, 2011; Hirota et al., 2013).
Accounting for about 20% of total hepatic CYP content,
CYP2C9 is the second highest expressed protein among all
CYP isoforms in human liver. It metabolizes a broad range
of structurally diverse therapeutic compounds, including
oral sulfonylurea hypoglycemics, antiepileptics, nonsteroidal
anti-inflammatory drugs (NSAIDs), anticoagulants, selec-
tive COX2 inhibitors, angiotensin II receptor inhibitors,
1
Cellular Biology and Molecular Genetics Laboratory, Faculty of Sciences, University Ibn-Zohr, Agadir, Morocco.
2
Human Genetics Laboratory, Life Sciences Faculty, University of Madeira, Funchal, Portugal.
GENETIC TESTING AND MOLECULAR BIOMARKERS
Volume 21, Number 5, 2017
ªMary Ann Liebert, Inc.
Pp. 1–7
DOI: 10.1089/gtmb.2016.0304
1
cyclophosphamide, and others (Rettie and Jones, 2005;
Zanger et al., 2008; Hirota et al., 2013). CYP2C19, although
expressed at rather low levels, plays a direct role in the me-
tabolism of clinically relevant drugs such as antidepressants,
benzodiazepines, anticonvulsants, proton pump inhibitors,
antiplatelet prodrug clopidogrel, proguanil, and other sub-
strates (Ingelman-Sundberg, 2004; Hirota et al., 2013; Zan-
ger and Schwab, 2013).
CYP2C9 and CYP2C19 genes exhibit high levels of ge-
netic polymorphisms in human populations, and it has been
demonstrated that alterations in the therapeutic response and
the development of adverse drugs effects are related to these
polymorphisms. Certain single nucleotide polymorphisms
have been shown to have a large impact on CYP2C9-19 ac-
tivity: CYP2C9*2 (430C>T, Arg144Cys) and CYP2C9*3
(1075A>C, Ile359Leu) are important alleles because they
encode a significant altered CYP2C9 activity and therefore
predispose individuals to enzyme sensitivity. These muta-
tions are the best characterized CYP2C9 alleles responsi-
ble for the CYP2C9 PM phenotype (Miners and Birkett,
1998; Goldstein, 2001; Rettie and Jones, 2005). Other al-
leles causing a defective phenotype are a variant encoding a
CYP2C19 protein completely lacking enzymatic activity,
CYP2C19*2, an 861G/A nucleotide substitution in exon 5
resulting in an aberrant splice site, and CYP2C19*3, a 636G/
A nucleotide substitution in exon 4 producing a premature
stop codon. Most metabolism deficiency of CYP2C19 is at-
tributable to CYP2C19*2 and CYP2C19*3 null alleles (De
Morais et al., 1994a, 1994b; Goldstein et al., 1997).
Substantial differences in the genotype and allele fre-
quencies of CYP2C9-19 defective variants between popula-
tions have been described. It is well known that CYP2C9-19
pharmacogenetic relevant alleles vary in frequencies de-
pending on ethnic and geographical origin (Goldstein et al.,
1997; Scordo et al., 2001; Garcı
´a-Martı
´net al., 2006; Dan-
dara et al., 2011; Martis et al., 2013; Vicente et al., 2014).
Such differences among populations really limit their po-
tential use as biomarkers of clinical importance since none
can act as a reference population against which all others can
be compared. Variants associated with altered enzymatic
activity can reach surprisingly high frequencies in certain
groups and, therefore it is important to obtain CYP2C9-19
pharmacogenetic relevant allele’s frequency data in each
population.
There is a huge gap in the Moroccan population concern-
ing the genetic content of CYP2C9 and CYP2C19 genes. This
study aims to describe the genetic profile of CYP2C9 and
CYP2C19 relevant alleles associated with deficiency in me-
tabolism of drugs that are usually prescribed in the treatment
of common diseases. For this purpose, we first determined the
CYP2C9 and CYP2C19 genotype profile of a Moroccan
population by screening for the main allelic variants and
compared our results with previous findings in other Medi-
terranean as well as African and Oriental populations. Sec-
ondly, we examined whether these mutations account for the
CYP2C9-CYP2C19 PM status in our population.
Materials and Methods
Population sample
Our sample consisted of 290 healthy subjects; all of them
students at Ibn Zohr University (Agadir, south of Morocco).
The subjects are originated from Souss, a South-eastern re-
gion of Morocco, and are descendants of original autoch-
thonous inhabitants of this region. A written informed consent
to participate in the study was obtained from the volunteers.
Venous blood was collected, and genomic DNA was ex-
tracted using a standard salting out procedure, as described
elsewhere (Miller et al., 1988).
Genotyping for CYP2C9 and CYP2C19
The most common allele, considered as the wild-type for
CYP2C9/19, is denoted CYP2C9/19*1, and the two main
defective alleles, accounting for the majority of PM pheno-
types, are CYP2C9/19*2 and CYP2C9/19*3.
As the CYP2C19 and CYP2C9 genotype is correlated with
the phenotype, CYP2C9/19 genotypes were therefore clas-
sified into three phenotypes:
Extensive metabolizers (EMs) carrying normal function
alleles (*1/*1)
Intermediate metabolizers (IMs) carrying one loss-of-
function allele (*1/*2, *1/*3)
Poor metabolizers (PMs) carrying two loss-of-function
alleles (*2/*2, *2/*3, *3/*3)
The molecular typing of CYP2C9/19 alleles was conducted
by a polymerase chain reaction (PCR)-restriction fragment
length polymorphism analysis according to the protocol de-
scribed elsewhere (Ferguson et al., 1998; Yasar et al., 1999;
Xie et al., 2002) with minor modifications.
To identify CYP2C9*2 and CYP2C9*3 polymorphisms,
reaction mixtures of 15 mL contained 1·buffer, 200 mM of
each nucleotides, 200 nM of each specific primers for exon 3
(5¢-CACTGGCTGAAAGAGCTAACAGAG-3¢and 5¢-GTG
ATATGGAGTAGGGTCACCCAC-3¢) and exon 7 (5¢-TGC
ACGAGGTCCAGAGGTAC-3¢and 5¢-ACAAACTTACCT
TGGGAATGAGA-3¢) respectively, 1 unit of Taq polymer-
ase, 100 ng of genomic DNA, and sterile milliQ water were
processed for PCR. Amplified PCR products were digested
with restriction enzymes AvaII for identifying CYP2C9*2 or
KpnI for CYP2C9*3 and the products were resolved in 3%
agarose gels. If the alleles genotyped were CYP2C9*1 or
CYP2C9*3, the 375 bp PCR products generated using prim-
ers for exon 3 were cleaved by AvaII into two fragments of
296 and 79 bp respectively. The CYP2C9*2 allele was re-
sistant to cleavage and remained at 375 bp. PCR products
generated using primers for exon 7 were 105 bp, which is the
correct size for alleles CYP2C9*1 and CYP2C9*2. The
CYP2C9*3 allele is still cleaved into two fragments of 85 and
20 bp when digested by KpnI.
For amplification of CYP2C19*2 or CYP2C19*3 alleles,
we used primers flanking intron 4 and exon 5 (5¢-CAGAG
CTTGG CATATTGTATC-3¢and 5¢-GTAAACACACAAC
TAGTCAATG-3¢) or primers flanking exon 4 (5¢-AAATTG
TTTCCAATCATTTAGCT-3¢and 5¢-ACTTCAGGGCTTG
GTCAATA-3¢) respectively. Fifteen microliters of reaction
mixture containing 1·buffer, 200 mM of each nucleotide,
200 nM of each primer, 1 unit of Taq polymerase, 100 ng of
genomic DNA, and sterile milliQ water were processed
for PCR. Amplified PCR products were digested with SmaI
or BamHI for identifying CYP2C19*2 and CYP2C19*3 re-
spectively and the products were resolved by 3% agarose
gels. A SmaI restriction site is encoded by the wild-type
2 AFILAL ET AL.
CYP2C19*1 allele (212 and 109 pb), while the variant allele
CYP2C19*2 abolishes this restriction site. Therefore, the
presence of CYP2C19*2 can be determined by the lack of
SmaI mediated digestion of the (PCR) product (321 pb) that
contains this site. For the CYP2C19*3 allele resulting in the
loss of the BamHI recognition site (271 pb), the only samples
containing CYP2C19*1 wild-type and CYP2C19*2 variants
can be cleaved by BamHI (175 and 96 pb).
For quality control, randomly 15–20% of the samples were
selected and regenotyped to confirm the authenticity of the
results obtained earlier and all were found to be in perfect
concordance.
Statistical analysis
Data were compiled according to the genotype and allele
frequencies estimated from the observed numbers of each
specific allele. The incidence of the different phenotypes
status (EM, IM, and PM) in our population was also assessed.
These analyses were performed using Arlequin version 3.5
software (Excoffier and Lischer, 2010). The XLSTAT (ver-
sion 2015.6) software was used for principal component
analysis (PCA).
Chi-squared tests (w
2
) were used for comparisons of
allele and genotype frequencies. Deviations from Hardy–
Weinberg equilibrium (HWE) for allele and genotype
frequencies for the various single-nucleotide polymor-
phisms were assessed by Fisher’s exact test. A pvalue
below 0.05 was considered statistically significant throughout
the population comparisons.
Results and Discussion
Description of allele and genotype frequencies found in
our South Moroccan population is presented in Table 1. Al-
lele and genotype frequencies for the CYP2C9-19 variants
were in HWE. Allele frequencies of these polymorphisms
were then compared to data reported for different worldwide
populations including Mediterraneans, sub-Saharans, and
Asians (Tables 2 and 3).
This study shows an allelic frequency of 88.62% for the
wild-type allele CYP2C19*1 and 11.38% for the CYP2C19*2
loss-functional variant. The 2C19*3 mutation was not de-
tected in any of the subjects. The frequency of IM phenotype
2C19*1/2C19*2 was found to be high (22.07%) when com-
pared to the PM phenotype 2C19*2/2C19*2 (0.34%) that was
rare in our sample. The null-allele 2C19*2 appears to be the
most prevalent allele associated with IM and PM phenotypes
in our population.
The most frequent CYP2C9 alleles in the studied Mor-
occan population were CYP2C9*1 and *2, occurring
with frequencies of 90.52% and 9.48% respectively. The
CYP2C9*3 mutation was not detected in our sample. In what
concerns the CYP2C9 genotype distribution, 242 subjects
(83.45%) were categorized as EMs, and only 41 subjects
(14.14%) were IMs. Only seven subjects (2.41%) had a ge-
notype (CYP2C9*2/CYP2C9*2) indicative of poor metabo-
lism. The defective allele CYP2C9*2 appears to be the most
prevalent allele associated with the PM phenotype.
Significant differences are known to exist in the distribu-
tion of the variant alleles and genotype of CYP2C9-19 across
worldwide populations. Caucasian populations are charac-
terized by the highest frequencies of the common decreased-
function variants of CYP2C9, while the altered activity
variants in other populations are rarer (Wang et al., 1995;
Scordo et al., 2001; Xie et al., 2002; Takahashi et al., 2003;
Garcı
´a-Martı
´net al., 2006; Scott et al., 2010; Dandara et al.,
2011; Martis et al., 2013), suggesting that it is only phar-
macogenetically relevant in Mediterranean populations.
CYP2C9*2 variant is virtually absent in Asians and absent or
very rare in sub-Saharans, whereas it is the most common
defective allele among Caucasians. The frequency of this
allele in our population was 9.48% a value not so dif-
ferent from those reported for Caucasian populations. The
CYP2C9*3 defective allele was not detected in Moroccans
and was very rare or absent in sub-Saharans, although it was
common in Caucasian populations (Table 2). The 2C9*1/*3
and 2C9*2/*3 genotypes are more prevalent in Europeans
(10–16% and 2–8%) than in Asians (3–8% and 0%), and
absent in Africans. Although the 2C9*1/*2, 2C9*2/*2, and
2C9*3/*3 genotypes frequency was very low or not detect-
able in Africans and Asians, it appears to be in a higher
range and specific among Caucasians. These genotypes ac-
count for almost 2C9-PMs in Caucasians than other popu-
lations (Sipeky et al., 2009; 1000GENOMES:phase_3).
The CYP2C19 has also shown the most striking pattern of
interethnic variation. The null function variant CYP2C19*2
is distributed in different ethnic groups at a relatively high
frequency, and is more frequently observed in Asians than in
Europeans or sub-Saharans (Table 3), probably indicating
that this detrimental mutation is relatively ‘‘ancient,’’ and
occurred before the split in African, Asian, and Caucasian
population groups. In contrast, the absence of CYP2C19*3
mutation in Moroccans and other non-Oriental populations
further illustrates the ethnical difference between Mediter-
ranean and Asian populations, by confirming the Asian
specificity of this allelic variant (Table 3). The 2C19 geno-
type frequency tends to decrease from East to West. The
prevalence of 2C19*1/*2, 2C19*1/*3, and 2C19*2/*2 ge-
notypes observed in our study of healthy Moroccan subjects
was very close to that found in Africans and Caucasian
populations, but proved to be lower than in Orientals. The
genotypes 2C19*2/*3 and 2C19*3/*3, responsible of the PM
phenotype, are specific to Asian populations (Desta et al.,
2002; 1000GENOMES:phase_3).
Table 1. Allele and Genotype Frequency
Distribution and the Predicted Phenotype (%)
of CYP2C9 and CYP2C19 in the Healthy South
Moroccan Population Sample
CYP2C9 CYP2C19
Allele frequency
*1 90.52 88.62
*2 9.48 11.38
*3 — —
Phenotype
(EM) wt/wt *1/*1 83.45 77.59
(IM) wt/mut *1/*2 14.14 22.07
(PM) mut/mut *2/*2 2.41 0.34
EM, extensive metabolizer; IM, intermediate metabolizer; mut/
mut, homozygous mutant; PM, poor metabolizer; wt/mut, hetero-
zygous mutant; wt/wt, homozygous wild-type.
CYP2C9 AND CYP2C19 GENE POLYMORPHISMS IN MOROCCANS 3
As CYP2C9/19*3 polymorphisms were not observed in
our population (either they are absent or present at very low
frequencies) CYP2C9/19*2 are likely to substantially con-
tribute to the population intra-variability of CYP2C9-19
found. Regarding CYP2C9*2 and CYP2C19*2, about 16%
and 22% of Moroccans are deficient metabolizers and
3.1% individuals are with combined genotype CYP2C9*2/
CYP2C19*2, thus they completely or largely lack this en-
zymatic activity. Deficient metabolizers utilize substrates
of CYP2C9-19 considerably slower, which implies higher
plasma levels and thus a risk of having excessive or pro-
longed therapeutic effect, and experiencing more drug-
related toxicity after a normal dose is administrated. In those
cases of patients treated with prodrugs (clopidogrel, pro-
guanil, cyclophosphamide, among others), which requires
activation by enzymes, these individuals may experience less
Table 2. The Observed CYP2C9 Allele Frequencies (%) for This Moroccan Population
and the Known Allele Frequencies for African, Caucasian, and Asian Populations
Populations
CYP2C9 frequency
ReferencesN*1 *2 *3
Moroccan 290 90.52 9.48 — Current study
Jordanian 290 79.7 13.5 6.8 Yousef et al. (2012)
Saudi Arabia 131 84.4 13.3 2.3 Alzahrani et al. (2013)
Lebanese 161 79.2 11.2 9.6 Djaffar-Jureidini et al. (2011)
Egyptian 247 81.8 12 6.2 Hamdy et al. (2002)
Turkish 499 79.4 10.6 10.0 Aynacioglu et al. (1999b)
Italian 360 77.8 12.5 9.7 Scordo et al. (2004)
Spaniard 282 86.9 13.3 7.7 Vicente et al. (2014)
German 118 81 14 5 Burian et al. (2002)
Greek 283 79 12.9 8.1 Arvanitidis et al. (2007)
French 151 77.2 14.9 7.9 Yang et al. (2003)
Belgian 121 82.2 10 7.4 Allabi et al. (2003)
Portugal 135 78.8 13.2 8 Oliveira et al. (2007)
Ethiopian 150 94 4 2 Scordo et al. (2001)
Beninese 111 100 — — Allabi et al. (2003)
Ghanaian 204 100 — — Kudzi et al. (2009)
Japanese 140 98 — 1.8 Kimura et al. (1998)
Chinese 115 98.3 — 1.7 Wang et al. (1995)
—, not detected.
Table 3. Distribution of CYP2C19 Allele’s Frequencies (%) in Moroccan Population
Compared to Other Worldwide Population
Populations
CYP2C19 frequency
ReferencesN*1 *2 *3
Moroccan 290 88.62 11.38 — Current study
Jordanian 290 87.7 12.3 — Yousef et al. (2012)
Saudi Arabia 97 85 15 — Goldstein et al. (1997)
Lebanese 161 86.3 13.4 0.3 Jureidini et al. (2011)
Gaza strip 200 91.2 5.8 3 Sameer
1
et al. (2009)
Egyptian 247 88.8 11 0.2 Hamdy et al. (2002)
Turkish 404 88 12 0.4 Aynacioglu et al. (1999a)
Greek 283 87 13 — Arvanitidis et al. (2007)
German 765 86.5 13.3 0.2 Tamminga et al. (2001)
Italian 360 88.9 11.1 — Scordo et al. (2004)
Portuguese 135 86 14 — Oliveira et al. (2007)
Belgian 121 90.9 9.1 — Allabi et al. (2003)
Spaniard 282 86.9 12.8 0.3 Vicente et al. (2014)
Ethiopian 114 84.6 14 2 Persson et al. (1996)
Ghanaian 204 94 6 — Kudzi et al. (2009)
Tanzanian 195 90 10 — Bathum et al. (1999)
Zimbabwean 168 86.9 13.1 — Masimirembwa et al. (1995)
Beninese 111 87 13 — Allabi et al. (2003)
Japanese 140 54 35 11 Kimura et al. (1998)
Chinese 75 66.7 28.9 4.4 Morais et al. (1995)
—, not detected.
4 AFILAL ET AL.
therapeutic benefit than patients with a normal CYP2C9-19
function. These effects are more pronounced for drugs me-
tabolized mainly by CYP2C9 and/or CYP2C19 (Kirchheiner
and Brockmo
¨ller, 2005; Fukasawa et al., 2007; Carbonell
et al., 2010; Hirota et al., 2013).
The fact that relatively high frequencies of the CYP2C9/
19*2-deficient variants were detected in Moroccans, a special
attention is to be put by clinical practitioners when admin-
istrating drugs with severe toxicity and/or with a narrow
therapeutic index (anticoagulants, antiplatelets, antiepilep-
tics.). There is a growing evidence of negative potential
implications of CYP2C9*2/*3 and CYP2C19*2/*3 poly-
morphisms in the therapeutic efficacy and in the development
of adverse effects. This includes elevated risk of excessive
anticoagulation, serious bleedings, and higher rates of car-
diovascular complications from drugs used in the treatment
of cardiovascular diseases (antihypertensives, anticoagu-
lants, antiaggregating agents.) (Kirchheiner and Brock-
mo
¨ller, 2005; Simon, 2013; Ucar et al., 2013).
Several studies using different populations have demon-
strated the use of 2C9-19*2/*3 alleles as biomarkers in
monitoring and predicting drug response and adverse effects
of antidepressants, anticoagulants, antiplatelets, antiepilep-
tics, NSAIDs, and others ( Jonas and McLeod, 2009; Perry,
2011; Baumann et al., 2013; Rollason et al., 2014; B}
udi et al.,
2015; Gidal, 2015). CYP2C9-19 genotype testing can be very
useful in distinguishing between responders and nonre-
sponders for a specific drug treatment, identify patients at
high risk events, and eventually advising them to consider
other medications or alternative dosing strategies.
Interestingly, the frequency distribution of clinically rel-
evant alleles at CYP2C9-19 genes among our population
follows the patterns commonly found not only in Mediter-
raneans but also in sub-Saharans. Based on this frequency
distribution, a PCA shows that our Moroccan population
occupies an intermediate position between sub-Saharans and
south Europeans (Fig. 1). The pharmacogenetic profile of our
population was probably influenced by historical and de-
mographic events (e.g., gene flow) along the Mediterranean
and Sahara areas, which could contribute to the genetic di-
versity affecting drugs metabolism. Moreover, since
CYP2C9-19 enzymes are implicated in the metabolism of
environmental toxins and carcinogenic as well as endogenous
compounds such as steroidal hormones, selection might also
have played a role in the distribution of these genetic variants
in particular geographic locations.
Our results support the idea that allele frequencies of the
CYP2C9-19 metabolic genes are not randomly distributed
throughout human populations but follow diverse ethnic and
geographic-specific patterns. This could explain differences
in medication response and why adverse events may be rel-
evant or rarer in certain particular populations. In the case of
the specific CYP2C9-19 defective variant alleles, populations
with a high frequency are expected to be more prone to the
development of specific complications.
In addition to the differences shown by common variants
of these genes, there are many rare population/region-specific
alleles that also contribute to the genetic variation within and
among populations. In this study we focused on common
variants, and it will be interesting to see whether there are rare
or specific mutations in this particular southern Morocco
population, and thus investigate the possible implications in
relation to the observed metabolism deficiency. Although
studies have shown that genotyping of only few common
variants is sufficient to predict the major PM phenotype, in
Caucasians CYP2C19*2 accounts for 78% of the PM,
roughly the same (75%) in sub-Saharans (De Morais et al.,
1994b; Ibeanu et al., 1998; Xie et al., 1999; Goldstein, 2001).
FIG. 1. Principal compo-
nent analysis of the CYP2C9-
19 allele’s frequencies dis-
tribution on Mediterranean,
sub-Saharan, and Asian
populations.
CYP2C9 AND CYP2C19 GENE POLYMORPHISMS IN MOROCCANS 5
As these enzymes are involved in the metabolism of an
increasing list of drugs and with relatively high frequencies
of defective pharmacogenetic variants within CYP2C9-19*2
there are obvious medical consequences for our population,
especially in what concerns the treatment of disease within a
more general Moroccan health policy context. The results of
this study will provide a basis for future clinical studies and
will be useful for the future application of pharmacogenetics
and introduction of personalized pharmacotherapy in the
Moroccan population.
Acknowledgments
We would like to thank Dr. Abdellatif Aamoum (centre de
transfusion sanguine, Ho
ˆpital Hassan II, Agadir) for his help
in obtaining blood samples. This work was financially sup-
ported by Ibn Zohr University.
Author Disclosure Statement
No competing financial interests exist.
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Address correspondence to:
El Hassan Izaabel, PhD
Cellular Biology and Molecular Genetics Laboratory
Faculty of Sciences
University Ibn-Zohr
PO Box 8106
Agadir 80000
Morocco
E-mail: e.izaabel@uiz.ac.ma
CYP2C9 AND CYP2C19 GENE POLYMORPHISMS IN MOROCCANS 7
