A Mehmet Journal of Baki Cell Yokeş and Molecular Biology 7(1): 67-74, 2008
Haliç University, Printed in Turkey.
Paraoxonase-1 192 enzyme polymorphism in non-syndromic
clefting: In patients and parents
Gürsel Turgut 1 , Arzu Özcan 1,* , Ercan Çakmak 1 , Lütfü Baş 1 , Soner Tatlıdede 1 , Oğuz
Öztürk 2 , Bedia Ağaçhan 2 , Ümit Zeybek 2 and Arzu Ergen 2 .
Department of Plastic and Reconstructive Surgery, Sisli Etfal Researh and Educational Hospital, Istanbul,
Istanbul University, Institute for experimental medicine, Department of Molecular Medicine. Istanbul,
(*author for correspondence; email@example.com)
Received 20 November 2007; Accepted 19 June 2008
Most orofacial clefts are nonsyndromic, isolated defects, and are classified into two groups: cleft lip (CL)
with or without cleft palate and cleft palate (CP) only. Both are genetically complex traits, the genetic cause
is stil elusive, it is genetically complex and enviromental factors are also responsible for the pathogenesis.
Epithelial transformation to mesenchyme is an important event during the process of palatogenesis. Specifically,
epithelial-mesenchymal transformation is thought to be critical for the disappearance of the seam and
mesenchymal confluence. In palate formation, apoptosis is thought to facilitate adherence, or touching, of
the opposing epithelium to form a seam. Apoptosis is important to sculpt the organelles in the body during
development. We hypothesize that oxidative stress promotes epithelial cell apoptosis during palate formation.
Oxidative stress occurs when the production of reactive oxygen species (ROS), including free radicals,
exceeds the handling capability of intracellular antioxidant enzymes and extracellular antioxidant defenses.
Excessive oxidative stress leads to peroxidative damage to cells, altered cellular function, and pathologic
effects. Paraoxonase (PON) is a serum enzyme that is associated with antioxidant mechanism. We aim to
determine the prevalance of the PON-1 192 polymorphisms in the patients and control groups. All cases
included in this study are from the medical records of the Plastic, Reconstructive and Esthetic Clinic of Sisli
Etfal Research and Training Hospital from August 2004 to January 2006. 50 nonsyndromic CL and CP cases
and parent were analyzed. Blood specimens were collected in tubes containing EDTA, and DNA was prepared
from leucoycte pellet by SDS lysis ammonium acetate extraction and ethanol precipitation. PON-1
genotypes were determined following PCR according to previously published protocols. Paraoxonase activities
was measured according to Furlong et al. (1989). We evaluated the frequencies of polymorphisms of the
PON1-192 gene in nonsyndromic cleft lip and cleft palate patients and in matched control subjects.
Key Words: Cleft lip and palate, paraoxonase gene polymorphism, paraoxonase enzyme activity, reactive
oxygen species, peroxidative damage.
Sendromik olmayan yarık damak ve dudaklı hasta ve ailelerinde paraoksonaz-1 192
Review Article 67
Orofasyal yarıkların büyük çoğunluğu genellikle nonsendromiktir ve iki farklı gruba ayrılabilir: yarık damak
ile birlikte veya olmaksızın yarık dudak ve sadece yarık damak. Her ikisinin de genetik komponentleri oldukça
karmaşıktır, ayrıca çevresel faktörler de palatogenezde etkilidir ve bir genin veya lokusun izole
Gürsel Turgut et al.
edilmesi oldukça zordur. Özellikle epitelyal- mezenkim transformasyonu damak bütünlüğünün
sağlanmasında kritik bir olaydır. Damak formasyonunda, apoptoz birbirine karşılıklı gelen epitelin düzgün
damak yapısını oluşturmasını sağlamak için yapışmayı ve dokunmayı artırır. Apoptoz, vücutta gelişim
sırasında organelleri şekillendirmek için önemlidir. Damak formasyonunda oksidatif stresin epitelyal apoptoza
neden olabileceğini ileri sürmekteyiz. Reaktif oksijen ürünlerinin üretimi ile ve hücre içi antioksidatif
enzimlerin ve hücre dışı antioksidatif mekanizmaların aşılması ile oksidatif stres meydana gelir. Aşırı oksidatif
stres hücrede peroksidatif hasar oluşturur ve hücre fonksiyonunu değiştirerek patolojik etkilere neden
olur. Paraoksonaz enzimi antioksidatif mekanizmada etkili bir serum enzimidir.
Bu çalışmamızda oksidatif stres ve yarık dudak/damak palatogenezinde ilişkisini ve bu süreçte paraoksonaz
gen polimorfizminin rolünü açıklamayı amaçladık. Bu çalışmaya dahil edilen vakalar Şişli Etfal Eğitim ve
Araştırma Hastanesi Plastik, Rekonstrüktif ve Cerrahi Kliniğine Ağustos 2004 ile Ocak 2006 arasında
başvuran hastaların tıbbi kayıtlarından alındı. 50 sendromik olmayan yarık dudak ve damaklı hasta ve aileleri
incelendi. Kan örnekleri EDTA’lı tüplere alındıktan sonra DNA, lökositlerin SDA amonyum asetat lizisi
ile ekstraksiyonu ve etanol presipitasyonu ile hazırlandı. PON1 genotipleri daha önce yayınlanmış protokollere
göre PCR uygulamasını takiben belirlendi. Furlong (1989) tarafından uygulanan yönteme göre serumda
Paraoksonaz aktivitesi araştırıldı. Sendromik olmayan yarık dudak ve damaklı hastalarda ve kontrol
gruplarında PON-1 192 gen polimorfizminin sıklığını araştırdık.
Anahtar Sözcükler : Yarık dudak ve damak, paraoksonaz gen polimorfizmi, paraoksonaz enzim aktivitesi,
reaktif oksijen ürünleri, peroksidatif hasar.
Orofacial clefts are common birth defects with a
known genetic component to their etiology.
Orofacial clefts are classified as nonsyndromic
(isolated) or syndromic based on the presence of
other congenital abnormalities. Cleft lip and cleft
palate are two of the most common congenital
abnormalities, with a reported incidence of up to
1 in every 1000 live births (Das et al.,1995) Approximately
20–50% of all orofacial clefts are
associated with one of more than 400 described
syndromes(Forester et al., 2004). These syndromes
often have simple Mendelian inheritance
patterns and are thus amenable to gene identification.
Most orofacial clefts are nonsyndromic,
isolated defects, which can be separated into two
different phenotypes: cleft lip (Gorlin, 2001)
(CL) with or without cleft palate (Gorlin, 2001)
and cleft palate (CP) only. Both are genetically
complex traits, the genetic cause is stil elusive, it
is genetically complex and enviromental factors
are also responsible for the pathogenesis. The
molecular events that underlie the formation of
orofacial structures are under the strict control of
an array of genes that includes the fibroblast
growth factors (FGFS), sonic hedgehog (SHH),
bone morphogenetic proteins (BMPs), members of
the transforming growth factor β (TGF-β) superfamily,
and transcription factors such as Dlx,Pitx,
Hox, Gli and T-box families (Stanier et al., 2004).
Studies of orofacial clefting have shown that CL/P
has complex inheritance patterns as evidenced by a
positive family history for clefting in 33% of the
patients, with no clearly recognizable mode of
inheritance, and reduced penetrance (Wyszynski,
Birth defects are likely to recur in families not
only because of genetic factors but also as a result
of environmental factors (Murray, 2004). Cigarette
smoking during pregnancy, with the attendant hypoxia,
is associated with several adverse reproductive
outcomes. The most recent meta-Analysis on
the effects of smoking indicates a moderately increased
risk of orofacial clefts (Zeiger et al., 2005).
Maternal nutrition during pregnancy also appears
to play an important role. For example, low dietary
intake of B-complex vitamins, lower or excessive
dietary intake of vitamin A are among the factors
that are associated with the increased risk of cleft
formation (Little et al., 2004 and Finnell et al.,
2004). Increased risks from exposures can suggest
metabolic pathways whose disruption might
trigger the development of clefts. Several studies
have shown that folic acid and other B-complex
vitamins might have a beneficial effect on reducing
the risk of orofacial clefts (Mungeri, 2002 and
Botto et al., 2004).
Of particular importance to a complex trait
such as clefts is the study of the likely impact of
both genetic and environmental factors. Several
studies have investigated interactions of a range
of common environmental factors, such as cigarette
smoking, alcohol intake, multivitamin/folic
acid supplementation and the use of medication,
with variant alleles in several genes that include
TGFA, TGFB3, MSX1, BCL3, RARA, MTHFR,
CYP1A1, NAT1, NAT2, GSTT1 and EPHX
(Munger et al., 2004; Zeiger and Beaty, 2004).
Both apoptosis and epithelial mesenchymal
transformation play a major role in development
of palate. Apoptosis is important to sculpt the
organelles in the body during development.In
palate formation, apoptosis is thought to facilitate
adherence, or touching, of the opposing epithelium
to form a seam (Ferguso and Honig, 1984;
Martinez-Alvarez et al., 2000). Both inhibition of
cell death with a caspase inhibitor and acceleration
of cell death with retinoic acid result in cleft
palate in vitro (Cuervo et al., 2002 and Brunet et
al., 1995). Epithelial transformation to mesenchyme
is an important event during the process of
palatogenesis. Especifically, epithelialmesenchymal
transformation is thought to be
critical for the disappearance of the seam and
Paraoxonase-1 192 enzyme polymorphism 69
Table 1. Observed frequencies of the 192A and 192B alleles, and the AA, BB, and AB genotypes and paraoxonase
enzyme activity in general studying group, and controls.
PON-1 192 Polymorphism
AA BB AB
mesenchymal confluence. We hypothesize that
exposure to oxidative stress promotes epithelial cell
apoptosis during palate formation. Oxidative stress
occurs when the production of reactive oxygen
species (ROS), including free radicals, exceeds the
handling capability of intracellular antioxidant
enzymes and extracellular antioxidant defenses.
Factors that may increase oxidative stress include
smoking, infections and inflammation, lower levels
of antioxidant production, and toxic exposures
(Blackburn, 2005; Agarwal et al., 2003). Defective
fusion in embryonic primary or secondary palate
has been reported in several mouse embryos and
explants exposed to xenobiotics, e.g. drugs and
various environmental pollutants such as dioxins or
nicotine derivatives (Saito et al., 2005). Excessive
oxidative stress leads to peroxidative damage to
cells, altered cellular function, and pathologic effects.
Paraoxonase (PON) is a serum enzyme that is
associated with antioxidative mechanism. The
paraoxonase gene maps to chromosome 7 (q21-23)
and has three separate genes, PON-1, PON-2 and
PON-3 (Primo-Parmo et al.,1996). Paraoxonase, a
45 kDa glycoprotein, that detoxify organophosphates
(Costa et al., 1999). It also serves HDL
associated protein, and with this function it protects
LDL against oxidation (Aviram et al., 1998). PON
1 has also been described to be related to the attributed
HDL anti-apoptotic function, since the ability
of HDL to protect against apoptosis is completely
lost when lipoprotein is oxidized (Matsunaga et al.,
2001). Moreover, it has also been shown thaat the
anti-apoptotic capacity is completely lost when
HDL is oxidized, and the lipoprotein becomes
proapoptotic to human aortic endothelial cell cultures
(Matsunaga et al., 2001). PON1 has two
common polymorphisms at codon 192 and 55. The
Patient group 23 (29%) 14 (18%) 43 (54%) 80 (100%)
Control group 26 (49%) 6 (11%) 21 (40%) 53 (%100)
Total 49 (37%) 20 (15%) 64 (48%) 133 (%100)
A Gürsel Turgut et al.
192 glutamine (A)/arginine (B) polymorphism of
PON-1 gene is associated to enzyme activity and
also arginine 192 (B allele) isoform of enzyme
activity on reparing and detoxification processes
was more elevated in patients who have cardiologic
and diabetic problems (Ağaçhan et al.,
We analyzed PON-1 192 polymorphism in
cleft lip/palate patients and their family. The
purpose of this study was to assess the frequency
of polymorphisms of the PON1-192 genes in
nonsyndromic cleft lip and cleft palate patients
and matched control subjects.
Materials and methods
All cases included in this study are from the medical
records of the Plastic, Reconstructive and
Esthetic Clinic of Şişli Etfal Research and Training
Hospital from August 2004 to January 2006.
50 nonsyndromic CL and CP cases and parents
were analyzed according to the following
variables: general information (gender, month
and year of birth), cleft type, maternal age, familial
history (hypertansion, malignancy and
having conjenital abnormality), associated malformations,
distribution of birth month. 45
healthy children and parents were also examined
as a control group.
Genotyping method of the paraoxonase 192
Blood specimens were collected in tubes containing
EDTA, and DNA was prepared from leukoycte
pellet by SDS lysis, ammonium acetate extraction
and ethanol precipitation. PON1 genotypes were
determined following PCR according to previously
published protocols (Miller et al., 1988).
For the 192 polymorphism, sense primer 5'
TAT TGT TGC TGT GGG ACC TGA G 3' and
antisense primer 5' CAC GCT AAA CCC AAA
TAC ATC TC 3' which encompass the polymorphic
region of the human PON1 gene were used.
The PCR reaction mixture contained 100 ng DNA
template, 0.5 M of each primer, 1.5 mM MgCl2,
200 M dNTPs and 1 U Taq DNA polymerase (MBI
Fermentas). After denaturing the DNA for 5 min at
94°C, the reaction mixture was subjected to 35
cycles of denaturing for 1 min at 95°C, 1 min annealing
at 60°C and 1 min extension at 72°C. The
99 bp PCR product was digested with 8 U BspI
restriction endonuclease (MBI Fermentas, Lithuania)
overnight at 55°C and the digested products
were separated by electrophoresis on 4% agarose
gel and visualised using ethidium bromide. The Bgenotype
(arginine) contains a unique BspI restriction
site which results in 66 and 33 bp products and
the A-genotype (glutamine) will not be cut allowing
the PON1 192 genotype to be determined (Adkins
et al., 1993).
Figure 1. The B-genotype (arginine) contains a unique BspI restriction site which results in 66 and 33 bp products
and the A-genotype (glutamine) will not cut allowing the PON1 192 genotype to be determined. AA: 99bp, BB: 66
and 33 bp, AB: 99, 66, 33bp.
Paraoxonase enzyme activity
Paraoxonase activities was measured according to
Furlong ( Furlong et al.,1989). The assay buffer
contains 0.132 M Tris HCl (pH 8.5), 1.32 mM
CaCl2 and 2.63 M NaCl. Addition of 200 µl of 6
mM freshly prepared paraoxon (o,o-diethyl-o-pnitrophenylphosphate;
Sigma, Poole, UK) and 40
Ìl of serum initiated the assay. The rate of generation
of p-nitrophenol was determined at 37°C,
with the use of a continuously recording spectrophotometer
at 405 nm. A molar extinction coefficient
of 18.05 x 10 3 was used for calculation
using paraoxon as a substrate. Pararaoxonase
activity is expressed as units/liter.
The statistical analysis was performed using the
commercially available software program (SPSS
12.0, SPSS Inc., Chicago, IL, USA). Association
between the disease and genotypes were tested
with Pearson Chi-Square test and Two-Sample
Kolmogorov-Smirnov Test. A probability of less
than 0,05 was required for statistical significance.
We determined the frequencies for the 192A and
192B alleles; and the AA, BB, and AB genotypes
and paraoxonase enzyme activity in cleft lip/cleft
palate group, and controls (Table 1). AA genotype
was seen 33% in cleft lip/cleft palate group
and 32.5% in control group. AA genotype was
seen 48% in patients’s mothers and 24% in control
group’s mothers, and was seen 62.5% in
patients’s fathers and 28,8% in control group’s
fathers. BB genotype was seen 8.3% in cleft
lip/cleft palate group and 12.9% in control group,
and was seen 12% in patients’s mothers and 24%
in control group’s mothers. However it was seen
12.5% in patients’s fathers and 16.7% in control
group’s fathers. AB genotype was seen 58.3% in
cleft lip/cleft palate group and 54.8% in control
group and also was seen 40% in patients’s mothers
and 52% in control group’s mothers, however
was seen 25% in patients’s fathers and 52% in
control group’s fathers. There was no significant
differences in P192 genotype between mother,
father and children groups (Control group:
χ 2 =3.25, p=0.517; cleft lip/palate group: χ 2 =1.34,
p=0.855). There was no significant differences in
Paraoxonase-1 192 enzyme polymorphism 71
P192 genotype between case and control group
(χ 2 =5.70, p=0.058). When we assessed the P192
genotype randomly in mother, father and children
groups, there was no statistical difference (χ 2 =2.03,
There was no statistical difference between in
cleft lip/cleft palate patient and control group
z=1.03, p=0.236). There was no statistically difference
between in cleft lip/cleft palate patient’s
mothers group and control group ( z=0.84, p=0.46).
There was no statistically difference between in
cleft lip/cleft palate patient’s fathers group and
control group (z=0.84, p=0.46).
There were any relationship between PON-1
192 polymorphism and cleft lip/ cleft palate patients
and their parents. Our study found no significance
in PON1-192 allele or genotype frequency
in cleft lip/cleft palate patients.
Paraoxonase enzyme activity
Paraoxonase enzyme activity has been evaluated
both in study group and control groups by using
paired samples test (t= paired sample test value).
Mean paraononase enzyme values were 145
units/liter in cleft lip/cleft patient, were 200
units/liter and were 190 units/liter in cleft lip/cleft
palate patient’s mothers, were in control group’s
mothers 216 units/liter (SD: 97) and were 156
units/liter in cleft lip/cleft palate patient’s fathers,
were in control group’s fathers 202 units/liter.
There was no statistical difference between cleft
lip/cleft palate patients and control group in paraoxonase
enzyme activity (t= 1.65, p= 0.107). The
same holds for the cleft lip/cleft palate patient’s
mothers group and control group (t= 0.75, p=
0.475). There was also no statistical difference
between cleft lip/cleft palate patient’s fathers group
and control group in paraoxonase enzyme activity
(t= 0.75, p= 0.475).
Arginine 192 (B allele) isoform of enzyme activity
on reparing and detoxification processes was
more elevated in patients who have cardiologic and
diabetic problems (Ağaçhan et al., 2005). However
AA genotype which is associated with low enzyme
activity in cardiologic and diabetic patients
(Ağaçhan et al., 2005) were not seen both cleft
lip/cleft palate children and their parents. Also we
did not assessed any significant difference in paraoxonase
enzyme activity between cleft lip/cleft
palate patient and control group. However it is
difficult to explain paraoxonase enzyme activity
A Gürsel Turgut et al.
cause of the enzyme activity is affected by enviromental
changes and personal psycological condition.
We could not find the adequate laboratory
assessment in the enzyme levels in the literature.
The most important benefits of identifying the
genetic factors in disease susceptibility may not
be the potential for gene therapy, though it is an
exciting prospect. Rather, it should be the opportunity
for the treatment and prevention of clinical
disease by manuplating the enviroments of individuals
identified to be genetically at risk. The
low monozygotic concordance rate (25–50%) for
CL/P suggests that environmental factors are
involved. It is well recognized that alcohol (Murray,
2002) and smoking (Zeiger et al., 2005)
increase the risk for CL/P, and there is evidence
that folate supplementation decreases the risk
(Carmichael et al., 2003). Clearly it is likely that
the environment interacts with both the maternal
and fetal gene products, supporting the hypothesis
that genetic variation in involved pathways
modulates CL/P risk. Initial studies took a convenient
approach and looked for the interaction of
candidate genes and either smoking or alcohol.
Studies of gene-environment interaction in orofacial
clefting have evaluated candidate genes such
as TGFA, TGFB3, MSX1, BCL3, and RARA and
environmental behaviors including smoking,
alcohol use, and vitamin intake (Vieira et al.,
Myatt and Cui noted that pregnancy is a state
of oxidative stress arising from increased placental
mitochondrial (metabolic) activity and production
of ROS, mainly superoxide anion (Myatt and
Cui, 2004). Although maternal antioxidant capacity
increases during pregnancy, excessive oxidative
stress is seen in pregnancies complicated,
preterm labor, intrauterine growth restriction, and
miscarriage (Myatt and Cui, 2004). Excessive
oxidative stress leads to peroxidative damage to
cells, altered cellular function, and pathologic
effects. Paraoxonase is a serum enzyme that is
associated with antioxidative mechanism and is
well known for its ability to protect LDL against
oxidation. PON-1 has also been described to be
related to the attributed HDL antiapoptotic function,
since the ability of HDL to protect against
apoptosis is completely lost when lipoprotein is
oxidized. Moreover, it has also been shown thaat
the anti-apoptotic capacity is completely lost when
HDL is oxidized, and the lipoprotein becomes proapoptotic
to human aortic endothelial cell cultures
(Matsunaga et al., 2001). Taking these data together,
it may be hypothesized that PON-1 influences
the antiapoptotic ability of the HDL molecule. AA
genotype of PON-1 is associated with low enzyme
activity and in our study we have tried to explain
that there were any relationship between PON-1
192 polymorphism and cleft lip/ cleft palate patients
and their parents. Our study found no significance
in PON-1 192 allele or genotype frequency
in cleft lip/cleft palate patient. Also we did not
assessed any significant difference in paraoxonase
enzyme activity between cleft lip/cleft palate patient
and control groups. These results should be
interpreted with caution due to small numbers of
patients, but reinforces the need for very large scale
studies to provide a definitive answer.
Adkins S, Gan KN, Mody M and La Du BN.
Molecular basis for the polymorphic forms of
human serum paraoxonase/arylesterase:
glutamine or arginine at position 191, for the
respective A or B allozymes. Am J Hum Genet.
52: 598-608, 1993.
Agarwal A, Saleh RA, Bedaiwy MA. Role of reactive
oxygen species in the pathophysiology of
human reproduction. Fertil Steril. 79: 829–843,
Ağaçhan B.,Yılmaz H., Ergen A.,Karaali ZE, İsbir
T. Paraoxonase (PON1) 55 and 192 polymorphism
and its effects to oxidant-antioxidant system
in turkish patients with type 2 diabetes mellitus.
Physiol Res.54(3): 287-93, 2005.
Aviram M, Billecke S, sorenson R, Bisgaier C,
Newton R, Rosenblat m, Erogul j, Hsu C, Dunlop
C, La Du B: Paraoxonase Active Site required
for protection against LDL oxidation involves
its free sulfhydryl group and is different
from that required for its Arylesterase/Paraoxonase
activities: Selective Action Of
Human Paraoxonase Alloenzymes Q And R.
Arterio-Scler Thromb Vasc Biol. 18: 1617-
Blackburn S. Free radicals in perinatal and neonatal
care, part 1: the basics. J Perinat Neonatal
Nurs.19(4): 298-300, 2005.
Botto LD, Olney RS, Erickson JD: Vitamin supplements
and the risk for congenital anomalies
other than neural tube defects. Am J Med Genet.
125: 12-21, 2004.
Brunet, C.L., Sharpe, P.M., and Ferguson,
M.W.J. Inhibition of TGF-3 (but not TGF-_1
or TGF-_2) activity prevents normal mouse
embryonic palate fusion. Int. J. Dev. Biol. 39:
Carmichael SL, Shaw GM, Yang W, et al. Maternal
periconceptional alcohol consumption and
risk for conotruncal heart defects. Birth Defects
Res A Clin Mol Teratol. 67: 875-878,
Costa LG, Li WF, Richter RJ, Shih DM, Lusis A,
Furlong CE: The rol of paraoxonase (PON1)
in detoxification of orgonophosphates and its
human polymorphisms. Chem. Biol. Interact.119-120:
Cuervo, R.,Valencia, C., Chandraratna, R.A.S.,
and Covarrubias, L. Programmed cell death is
required for palate shelf fusion and is regulated
by retinoic acid. Dev. Biol. 245: 145,
Das, S.K., Runnel, R.S., Smith, J. C., and Cohlx,
H. H. Epidemiology of cleft lip and cleft palate
in Mississippi.South. Med. J. 88: 437,
Ferguson, M.W., and Honig, L.S. Epithelialmesenchymal
interactions during vertebrate
palatogenesis. In E. F. Zimmerman (Ed.),
Current Topics in Developmental Biology,
Vol. 19. Palate Development: Normal and
Abnormal, Cellular and Molecular Aspects.
New York: Academic Pres. 137-164, 1984.
Finnell RH, Shaw GM, Lammer EJ, Brandl KL,
Carmichael SL, Rosenquist TH: Gene-nutrient
interactions: importance of folates and retinoids
during early embryogenesis. Toxicol
ApplPharmacol 198:75-85, 2004.
Forrester MB, Merz RD. Descriptive epidemiology
of oral clefts in a multiethnic population,
Hawaii, 1986-2000. Cleft Palate Craniofac J;
Furlong CE, Richter RJ, Seidel SL, Costa LG,
Motulsky AG.Spectrophotometricassay for
the enzymatic hydrolysis of the active metabolites
of chlorpyrites and parathion by plasma
paraoxonase/arylesterase. Anal Biochemistry;
180: 242-7, 1989.
Gorlin RJ, Cohen MM, Hennekam RCM. Syndromes
of the head and neck. Oxford: Oxford
University Press; 2001.
Paraoxonase-1 192 enzyme polymorphism 73
Little J, Cardy A, Munger RG: Tobacco smoking
and oral clefts:a meta-analysis. Bull World
Health Organ. 82:213-218, 2004.
Martinez-Alvarez, C., Tudela, C., Perez-
Miguelsanz, J.,O’Kane, S., Puerta, J., and Ferguson,
M. W. J. Medial edge epithelial cell fate
during palatal fusion. Dev. Biol.220: 343, 2000
Matsunaga Y, Iguchi K, Nakajima Y, Koyama I,
Miyazaki T, Inoue I. Lycated high density induces
apoptosis of endothelial cells via a mithochondrial
dysfunction. Biochem Biophys Res
Miller SA, Dykes DD, Polesky HS. Simples salting
out procedure extracting DNA from human
nucleated cells. Nucleic Acid Res. 16/3: 1215,
Munger RG, Sauberlich HE, Corcoran C, Nepomuceno
B,Daack-Hirsch S, Solon FS: Maternal vitamin
B-6 and folate status and risk of oral cleft
birth defects in the Philippines. Birth Defects
Res A Clin Mol Teratol. 70:464-471, 2004.
Munger RG: Maternal nutrition and oral clefts. In
Cleft Lip and Palate: from Origin to Treatment.
Edited by Wyszynski DFE. Oxford University
pres. 170-192, 2002.
Murray J. Gene/environment causes of cleft lip
and/or palate. Clin Genet . 61:248-256, 2004.
Myatt L, Cui X. Oxidative stress in the placenta.
Histochem Cell Biol.122:369–382, 2004.Cui X.
Primo-Parmo SL, Sorenson RC, Teiber J, Du BNL;
The Human Serum Paraoxonase/Aryesterase
Gene (PON1) Is One Member of a Multigene
Family. Genomics. 33:498-507, 1996.
Saito T, Cui XM, Yamamoto T, Shiomi N, Bringas
Jr P, Shuler CF. Effect of N- nitrosonornicotine
(NNN) on murine palatal fusion in vitro. Toxicology;
Stanier P, Moore GE: Genetics of cleft lip and
palate: syndromic Hum Mol Genet, 13:73-81,
Vieira AR, Murray JC, Trembath D, et al. Studies
of reduced folate carrier 1 (RFC1) A80G and
(MTHFR) C677T polymorphisms with neural
tube and orofacial cleft defects. Am J Med Genet
A. 135:220-223, 2005.
Wyszynski DF. Cleft lip and palate: from origin to
treatment. Oxford: Oxford University Press;
Zeiger JS, Beaty TH, Liang KY. Oral clefts, maternal
smoking, and TGFA:a meta-analysis of
A Gürsel Turgut et al.
gene-environment interaction. Cleft Palate
Craniofac J. 42:58-63, 2005.
Zeiger JS, Beaty TH:Gene-environment interaction
and risk to oral clefts. In Cleft Lip and
Palate: from Origin to Treatment. Edited by
Wyszynski DFE. Oxford University pres.