A simple and cost-effective protocol for DNA isolation from buccal epithelial cells

Epigenetic mechanisms and oral mucositis in children with acute lymphoblastic leukaemia

This study aimed to investigate the relationship between epigenetic mechanisms and oral mucositis (OM) in paediatric patients with acute lymphoblastic leukaemia. Oral cells were collected from 76 participants, including 15 healthy individuals, 10 patients with acute lymphoblastic leukaemia but without a history of OM and 51 acute lymphoblastic leukaemia patients with a history of OM (35 with active OM and 16 who had recovered from OM). Global DNA methylation in the miR-9-1 and miR-9-3 genes was performed. Seven polymorphisms rs1801131, rs1801133 (MTHFR), rs2228611 (DNMT1), rs7590760, rs1550117 (DNMT3A), rs6087990, rs2424913 (DNMT3B) were genotyped and an analysis of association with global DNA methylation was performed. The global methylation levels were lower in cancer patients recovered from OM than in the other groups. A higher frequency of unmethylated profile for miR-9-1 and partially methylated profile for miR-9-3 was observed in cancer patients regardless of OM history compared to healthy patients. The GG genotype of the rs2228611 (DNMT1) polymorphism was associated with higher levels of global methylation in cancer patients irrespective of OM. It was concluded that global methylation is associated with mucosal recovery. The effect of DNMT1 genotype on the global DNA methylation profile, as well as the methylation profile of miR-9-1 and miR-9-3 in cancer patients is independent of OM.

Association between Angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on the susceptibility to psoriasis and oxidative stress (OS) in a cohort of pediatric psoriatic patients in Sri Lanka: A cross sectional study

Background

Pediatric psoriasis accounts for nearly one-third of the global psoriasis burden. Multiple lines of evidence have shown the relationship between Angiotensin-converting enzyme (ACE) Insertion (I)/deletion(D) polymorphism with psoriasis susceptibility, and oxidative stress (OS) in psoriatic patients. However, such studies, particularly on pediatric psoriasis, are scarce in the local setting.

Aims

Our study investigated the prevalence of ACE I/D polymorphism and its associations with oxidative stress in pediatric psoriasis patients in Sri Lanka.

Methods

Thirty patients were recruited for this study after obtaining ethical clearance. The polymerase chain reaction was used to explore the ACE I/D polymorphism. Serum Nitric Oxide (NO) levels and the Total Antioxidant Capacity (TAC) were measured using the Griess assay and the FRAP assay. Clinical details were obtained from the clinic reports.

Results

Female predominance (76.67%) in pediatric psoriasis was reported, while Plaque psoriasis (66.67%) was found to be the most prevalent form. I/D was reported as the predominant genotype (66.67%) while I/I and D/D genotypes were recorded in 23.33% and 10% of patients, respectively. Significantly higher NO levels were observed in I/D patients than in I/I patients but not among other groups. No differences in TAC among ACE genotypes were reported.

Conclusion

This pilot study revealed female gender and I/D genotype with increased NO levels as risk factors for pediatric psoriasis in Sri Lanka. However, it is prudent to increase the sample size to further validate the results.

Exploring etiologic contributions to the occurrence of external apical root resorption

INTRODUCTION

External apical root resorption (EARR) is often an undesirable sequela of orthodontic treatment. Prior studies have suggested a substantial link between EARR and certain genetic components. Single nucleotide polymorphisms (SNPs) may play a role as predisposing factors. This study aimed to investigate the potential association between EARR and various SNPs.

METHODS

The study included 218 orthodontic participants of all malocclusions who had available pretreatment and posttreatment panoramic radiographs. The most severely affected maxillary incisor on the radiograph was assessed for EARR using a 0-4 categorical scale. DNA was taken from the saliva samples of the participants, and the SNPs were analyzed using polymerase chain reaction and TaqMan chemistry. Statistical testing was performed to verify any associations with EARR (P <0.05).

RESULTS

From all genes tested, the rs678397 SNP of ACT3N (P = 0.003) and the rs1051771 SNP of TSC2 (P = 0.03) were significantly associated with EARR. No association could be established between other polymorphisms and EARR. In addition, patients with Class III malocclusion and extended treatment times were at increased risk of developing EARR.

CONCLUSIONS

Our results support the concept of gene polymorphisms as risk factors in EARR. In particular, a significant association was found between ACT3N and TSC2 and EARR. Clinically, predisposing risk factors for EARR should be assessed for each patient.

Association of HLA-DQ4/5 genotype polymorphisms with celiac disease in a group of children in Southwest Iran: A case-control study

Background and Aim

Celiac disease (CD) has proinflammatory and pathogenic immune responses to gluten in intestinal tissue, leading to structural changes in the mucosa of the small intestine. The association of human leukocyte antigen (HLA)-DQ2 and DQ8 genotypes with CD has been previously reported. This test has a negative predictive value close to 100%, so its main purpose is to rule out the detection of CD completely or almost completely. There is limited information regarding HLA-DQ4/5 in CD. This study was conducted to determine the HLA-DQ4/5 genotypes in a group of Southwestern Iranian children with CD.

Methods

We conducted a case-control study in Southwest Iran involving 100 participants, employing a nonprobabilistic sampling method. Samples were taken from participants' oral buccal mucosa at Imam Sajjad Hospital of Yasuj, Iran. Then DNA was extracted from these samples and used to determine the frequency of HLA-DQ4/5 genotypes through Sequence-Specific Primer-Polymerase Chain Reaction assay. SPSS 20 was utilized for statistical analyses.

Results

Fifty diagnosed patients with CD (high anti-tissue transglutaminase [tTG]-IgA level [upper limit of normal] with pathological findings of Marsh III) and 50 non-CD individuals (normal anti-tTG-IgA level and normal total IgA level) were enrolled in the study from August 5, 2022 to October 15, 2023. Findings showed that the DQ4a*4b allele has the highest frequency in the CD samples (78%, p < 0.01) followed by the DQ5a*5b allele (12%, p < 0.01). Additionally, there was a higher prevalence of DQ4/DQ5 in patients with CD compared to controls (odds ratio = 6.5, confidence interval = 0.84 to 69.46, p < 0.01). Furthermore, a significant association was found among HLA DQ4/5 genotype, age (>9.5) (p < 0.01), and gender (female) (p < 0.05).

Conclusion

The observed significant differences among HLA-DQ4 and HLA-DQ5 in Iranian CD samples against controls and the high value of the relative risks showed the significant function of the studied alleles in the prevalence of CD in Iranian patients.

Comparison of gender identification using exfoliated cells obtained from toothbrush and miswak: A longitudinal study

Gender identification plays a pivotal role in forensic medicine. Among the various methods used for gender identification, deoxyribose nucleic acid (DNA) based methods are considered accurate. Exfoliated oral mucosal cells that are harvested from oral hygiene aids can be potentially used for gender identification using real-time polymerase chain rection (PCR). The aim of the present longitudinal study is to assess and compare the efficacy of toothbrush and miswak as potential tools to harvest exfoliated cells for gender identification. Forty healthy volunteers were recruited and asked to clean their teeth using new toothbrush and fresh miswak each day for 4 days. Toothbrush and miswak used by the participants were subjected to DNA analysis immediately, 1st, 2nd and 6th month. The absorbance of DNA samples were quantified and gender identification was done by amplification of sex determining gene-Sex determining region Y gene (SRY) and ALT1 genes using real-time PCR. The number of correct and positive identification for samples at various time points were tabulated and subjected to statistical analysis. Post hoc power analysis showed that the study had a power of 93%. Correct and positive gender identification was observed for the samples (100%) obtained using miswak, for tooth brush it reduced to 95%, 80%, and 35% at the end of 1st, 2nd, and 6th month. The differences seen at the end of 2nd month and 6th month were statistically significant. Miswak is a better tool to harvest exfoliated cells for gender identification when compared to a toothbrush. Hence, miswak can serve as a potential tool in forensic medicine for DNA extraction and subsequently victim identification.

TNF-α promoter hypomethylation is frequent in oncopediatric patients who recovered from mucositis

The aim of this study was to investigate the DNA methylation profile in genes encoding catalase (CAT) and superoxide dismutase (SOD3) enzymes, which are involved in oxidative stress mechanisms, and in genes encoding pro-inflammatory cytokines interleukin-6 (IL6) and tumor necrosis factor-alpha (TNF-α) in the oral mucosa of oncopediatric patients treated with methotrexate (MTX®). This was a cross-sectional observational study and the population comprised healthy dental patients (n = 21) and those with hematological malignancies (n = 64) aged between 5 and 19 years. Oral conditions were evaluated using the Oral Assessment Guide and participants were divided into 4 groups: 1- healthy individuals; 2- oncopediatric patients without mucositis; 3- oncopediatric patients with mucositis; 4- oncopediatric patients who had recovered from mucositis. Methylation of DNA from oral mucosal cells was evaluated using the Methylation-Specific PCR technique (MSP). For CAT, the partially methylated profile was the most frequent and for SOD3 and IL6, the hypermethylated profile was the most frequent, with no differences between groups. For TNF-α, the hypomethylated profile was more frequent in the group of patients who had recovered from mucositis. It was concluded that the methylation profiles of CAT, SOD3, and IL6 are common profiles for oral cells of children and adolescents and have no association with oral mucositis or exposure to chemotherapy with MTX®. Hypomethylation of TNF-α is associated with oral mucosal recovery in oncopediatric patients who developed oral mucositis during chemotherapy.

MMP-1, MMP-8, and MMP-13 Gene Polymorphisms and Haplotype Is a Risk Factor for Dupuytren Contracture: A Case-Control Study

BACKGROUND

There is an increased tissue expression of matrix metalloproteinases (MMPs) on Dupuytren contracture (DC). Genetic polymorphisms (single nucleotide polymorphism [SNPs]) in genes of these enzymes may individually influence these transcriptions. Haplotype analysis, which is the observation of a group of alleles, could be more useful to identify the association between SNPs and DC. The purpose of this study was to evaluate the influence of MMP-1 g.-1607 G>GG (rs1799750), MMP-8 g.-799 C>T (rs11225395), and MMP-13 g.-77 A>G (rs2252070) SNPs individually and in haplotype on DC.

METHODS

A total of 60 patients with a clinical diagnosis of DC were evaluated and matched, according to age and gender, with the control group of 100 patients without this clinical diagnosis. Genomic DNA was extracted from saliva samples, and genotypes were obtained by polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis of the results included Mann-Whitney U test, Chi-squared test, and PHASE and R software, with a significance level of 5%.

RESULTS

The 3 SNPs studied showed significant differences in allele and genotype frequencies between the groups: 2G in MMP-1 (P = .018; odds ratio [OR] 1.80 (95% confidence interval [CI], 1.13-2.88)), T in MMP-8 (P = .015; OR 0.53 (95% CI, 0.33-0.88)), and A in MMP-13 (rs2252070) SNPs (P = .040, OR 0.54 (95% CI, 0.33-0.90)) are risk alleles. The global haplotype analysis indicated a significant difference between both groups.

CONCLUSIONS

In conclusion, MMP-1 g.-1607 G>GG (rs1799750), MMP-8 g.-799 C>T (rs11225395), and MMP-13 g.-77 A>G (rs2252070) SNPs, individually and in haplotype, are a risk factor for DC, indicating that these SNPs may be a potential diagnostic and prognostic factor for DC.

Characterization of non-invasive oropharyngeal samples and nucleic acid isolation for molecular diagnostics

Molecular diagnostics is an increasingly important clinical tool, especially in routine sampling. We evaluated two non-invasive methods (oral swabs and mouthwashes) for sampling nucleic acids from the oral/pharyngeal area. We created a workflow from sample collection (n = 59) to RT-qPCR based analysis. The samples were further characterized in terms of their cellular composition as well as the purity, degradation and microbial content of the derived DNA/RNA. We determined the optimal housekeeping genes applicable for these types of samples. The cellular composition indicated that mouthwashes contained more immune cells and bacteria. Even though the protocol was not specifically optimized to extract bacterial RNA it was possible to derive microbial RNA, from both sampling methods. Optimizing the protocol allowed us to generate stable quantities of DNA/RNA. DNA/RNA purity parameters were not significantly different between the two sampling methods. Even though integrity analysis demonstrated a high level of degradation of RNA, corresponding parameters confirmed their sequencing potential. RT-qPCR analysis determined TATA-Box Binding Protein as the most favorable housekeeping gene. In summary, we have developed a robust method suitable for multiple downstream diagnostic techniques. This protocol can be used as a foundation for further research endeavors focusing on developing molecular diagnostics for the oropharyngeal cavity.

Comparison of different DNA preservation solutions for oral cytological samples

OBJECTIVE

The objective of this study was to compare the DNA preservation capacity of buccal mucosa exfoliated cells when stored in different solutions under varying time and temperature conditions.

DESIGN

DNA preservation solutions, including Dimethyl sulphoxide disodium-EDTA-saturated NaCl (DESS), Tris-EDTA-NaCl-Tween20 buffer (TENT), Nucleic Acid Preservation Buffer (NAP), and phosphate-buffered saline (PBS), were prepared. Buccal mucosa cells from a single patient were collected, dispensed into these solutions, and stored at room temperature (RT) and 4 °C for 24 h, 72 h, 30 days, 90 days, and 180 days. DNA was extracted using the salting-out method and the QIAamp DNA Mini Kit. DNA concentration and purity were determined using the QuBit device and NanoDrop, while DNA integrity was assessed using the Agilent 4200 TapeStation system. The ability to amplify the IFNA primer was also evaluated by PCR.

RESULTS

The salting-out method yielded better concentration and purity results, with PBS, TENT, and DESS buffers demonstrating superior concentration values when stored at 4 °C, resulting in mean values exceeding 10 ng/μL for up to 30 days. DESS consistently exhibited the best integrity values over time for both temperature conditions. Amplification capacity was enhanced when samples were stored at 4 °C. When stored at RT, PBS achieved 100% amplification within 24 h. NAP yielded the poorest results.

CONCLUSION

In the context of long-term preservation, the DESS buffer emerges as the most effective solution, maintaining requisite DNA quality and quantity standards for up to 30 days at RT and up to 3 months at 4 °C.

Evaluation of clinical and genetic factors in obstructive sleep apnoea

Purpose

To evaluate the correlation between several presumed candidate genes for obstructive sleep apnoea (OSA) and clinical OSA phenotypes and propose a predictive comprehensive model for diagnosis of OSA.

Methods

This case-control study compared polysomnographic patterns, clinical data, morbidities, dental factors and genetic data for polymorphisms in PER3, BDNF, NRXN3, APOE, HCRTR2, MC4R between confirmed OSA cases and ethnically matched clinically unaffected controls. A logistic regression model was developed to predict OSA using the combined data.

Results

The cohort consisted of 161 OSA cases and 81 controls. Mean age of cases was 53.5 ± 14.0 years, mostly males (57%) and mean body mass index (BMI) of 27.5 ± 4.3 kg/m2. None of the genotyped markers showed a statistically significant association with OSA after adjusting for age and BMI. A predictive algorithm included the variables gender, age, snoring, hypertension, mouth breathing and number of T alleles of PER3 (rs228729) presenting 76.5% specificity and 71.6% sensitivity.

Conclusions

No genetic variant tested showed a statistically significant association with OSA phenotype. Logistic regression analysis resulted in a predictive model for diagnosing OSA that, if validated by larger prospective studies, could be applied clinically to allow risk stratification for OSA.

Polymorphisms in hormonal-related genes might be associated with variations in permanent tooth crown size

BACKGROUND

The variability in tooth crown size (TCS) is influenced by genetic factors and might be regulated by the difference in hormonal response.

MATERIALS AND METHODS

This study aimed to evaluate the association between variations in TCS of permanent teeth with associated factors and genetic polymorphisms in hormonal-related genes (ESR1, ESR2 and PTH). This cross-sectional study involved dental casts from 86 individuals of both sexes. Dental casts were used to determine the maximum TCS of all fully erupted permanent teeth (except third molars) in the mesiodistal (MD) and buccolingual (BL) dimensions. Data such as sex, ethnicity, dental group (incisor, canine, premolar and molar), dental arch (upper and lower) and genetic polymorphisms of hormonal-related genes were used. The DNA from each patient was collected to evaluate the genetic polymorphisms in ESR1 (rs2234693 and rs9340799), ESR2 (rs1256049 and rs4986938) and PTH (rs694, rs6256 and rs307247) through real-time PCR. The data were submitted to statistical analysis with a significance level of 0.05.

RESULTS

In the MD dimension, the sex, dental group and dental arch were associated with variation in TCS (P < .05). In the BL dimension, the sex, dental group, dental arch and polymorphism in rs694 and rs307247 were associated with variation in TCS.

CONCLUSIONS

In short, this study suggests that genetic polymorphisms of PTH are associated with variations in the BL TCS of permanent human teeth.

Comparison of DNA extraction methods for COVID-19 host genetics studies

The coronavirus disease 2019 (COVID-19) pandemic has resulted in global shortages in supplies for diagnostic tests, especially in the developing world. Risk factors for COVID-19 severity include pre-existing comorbidities, older age and male sex, but other variables are likely play a role in disease outcome. There is indeed increasing evidence that supports the role of host genetics in the predisposition to COVID-19 outcomes. The identification of genetic factors associated with the course of SARS-CoV-2 infections relies on DNA extraction methods. This study compared three DNA extraction methods (Chelex®100 resin, phenol-chloroform and the QIAamp DNA extraction kit) for COVID-19 host genetic studies using nasopharyngeal samples from patients. The methods were compared regarding number of required steps for execution, sample handling time, quality and quantity of the extracted material and application in genetic studies. The Chelex®100 method was found to be cheapest (33 and 13 times cheaper than the commercial kit and phenol-chloroform, respectively), give the highest DNA yield (306 and 69 times higher than the commercial kit and phenol-chloroform, respectively), with the least handling steps while providing adequate DNA quality for downstream applications. Together, our results show that the Chelex®100 resin is an inexpensive, safe, simple, fast, and suitable method for DNA extraction of nasopharyngeal samples from COVID-19 patients for genetics studies. This is particularly relevant in developing countries where cost and handling are critical steps in material processing.

The mutational analysis of mitochondrial DNA in maternal inheritance of polycystic ovarian syndrome

Introduction

Polycystic Ovarian Syndrome (PCOS) is a globally prevalent condition that leads to infertility in women. While environmental factors contribute to PCOS, maternal genetics also play a significant role. Currently, there is no definitive test for identifying predisposition to PCOS. Hence, our objective is to discover novel maternal genetic risk factors for PCOS by investigating the genomes of patients from Pakistan.

Methods

We utilized Next-Generation Sequencing (NGS) to sequence the complete mitochondrial DNA of three PCOS patients. Subsequently, we employed MitoTIP (Mitochondrial tRNA Informatics Predictor) and PON-mt-tRNA tools to identify variations in the mitochondrial DNA. Our analysis focused on the genes MT-RNR1, MT-RNR2, MT-ATP6, MT-TL2, and MT-CYTB, which displayed common variations in all three genomes. Additionally, we observed individual variations. The D-loop region exhibited the highest frequency of mutations, followed by the non-coding regions of RNR1 and RNR2 genes. Moreover, we detected frameshift mutations in the mitochondrially encoded NADH Dehydrogenase 2 (MT-ND2) and mitochondrially encoded NADH Dehydrogenase 5 (ND5) genes within individual genomes.

Results

Our analysis unveiled six regions with common variations in the mitochondrial DNA of all three PCOS patients. Notably, the MT-RNR1, MT-RNR2, MT-ATP6, MT-TL2, and MT-CYTB genes exhibited these variations. Additionally, we identified individual variations in the mitochondrial DNA. The D-loop region displayed the highest mutation frequency, followed by the non-coding regions of RNR1 and RNR2 genes. Furthermore, frameshift mutations were detected in the MT-ND2 and ND5 genes within individual genomes.

Conclusion

Through our study, we have identified variations in mitochondrial DNA that may be associated with the development of PCOS and have the potential to serve as predisposition tests. Our findings highlight the presence of novel mutations in the MT-RNR1, MT-RNR2, MT-ATP6, MT-TL2, and MT-CYTB genes, as well as frameshift mutations in the MT-ND2 and ND5 genes. Pathogenicity analysis indicated that most variants were likely to result in benign cysts. However, the frameshift mutations in the ND2 gene were associated with a high risk of complications and pathogenicity in PCOS. This is the first report identifying these mutations and their association with PCOS, contributing to our understanding of the genetic factors underlying the condition.

DNA Methyltransferase Genes Are Associated with Oral Mucositis and Creatinine Levels in Oncopediatric Patients

The aim of this study was to investigate the association of single-nucleotide polymorphisms (SNPs) and the DNA methylation profiles of the DNA methyltransferase (DNMT) gene family with oral mucositis in children and adolescents with hematologic malignancies treated with methotrexate (MTX®). The population was comprised of healthy and oncopediatric patients aged between 4 and 19 years. An evaluation of oral conditions was performed using the Oral Assessment Guide. Demographic, clinical, hematological, and biochemical data were obtained from medical records. Genomic DNA extracted from oral mucosal cells was used for the analysis of polymorphisms in DNMT1 (rs2228611), DNMT3A (rs7590760), and DNMT3B (rs6087990) using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique (n = 102) and for DNA methylation using the methylation-specific PCR (MSP) technique (n = 85). The allele and genotypic frequencies of SNPs did not reveal any differences between patients with or without oral mucositis. An increase in the methylation frequency for DNMT1 in patients recovered from mucositis was detected. The DNMT3A methylated profile associated with the CC genotype (SNP rs7590760) appeared to be connected to higher values of creatinine. In addition, the DNMT3B unmethylated profile associated with the CC genotype (SNP rs6087990) appeared to be connected with higher values of creatinine. We conclude that the DNMT1 methylation profile is associated with the post-mucositis period and that the genetic and epigenetic profiles of DNMT3A and DNMT3B are associated with creatinine levels.

A Pilot Study of Dietetic, Phenotypic, and Genotypic Features Influencing Hypertensive Disorders of Pregnancy in Women with Pregestational Diabetes Mellitus

Hypertensive disorders of pregnancy (HDP) are a leading cause of maternal and perinatal morbimortality. Dietetic, phenotypic, and genotypic factors influencing HDP were analyzed during a nutrigenetic trial in Rio de Janeiro, Brazil (2016-2020). Pregnant women with pregestational diabetes mellitus (n = 70) were randomly assigned to a traditional or DASH diet group. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured during prenatal visits and HDP were diagnosed using international criteria. Phenotypic data were obtained from medical records and personal interviews. Genotyping for FTO and ADRB2 polymorphisms used RT-PCR. Linear mixed-effect models and time-to-event analyses were performed. The variables with significant effect on the risk for progression to HDP were: black skin color (adjusted hazard ratio [aHR] 8.63, p = 0.01), preeclampsia in previous pregnancy (aHR 11.66, p < 0.01), SBP ≥ 114 mmHg in the third trimester (aHR 5.56, p 0.04), DBP ≥ 70 mmHg in the first trimester (aHR 70.15, p = 0.03), mean blood pressure > 100 mmHg (aHR 18.42, p = 0.03), and HbA1c ≥ 6.41% in the third trimester (aHR 4.76, p = 0.03). Dietetic and genotypic features had no significant effect on the outcome, although there was limited statistical power to test both.

Evidence Linking PPARG Genetic Variants with Periodontitis and Type 2 Diabetes Mellitus in a Brazilian Population

The peroxisome proliferator-activated receptor gamma (PPARG) gene encodes a transcription factor involved in the regulation of complex metabolic and inflammatory diseases. We investigated whether single nucleotide polymorphisms (SNPs) and haplotypes of the PPARG gene could contribute with susceptibility to develop periodontitis alone or together with type 2 diabetes mellitus (T2DM). Moreover, we evaluated the gene-phenotype association by assessing the subjects' biochemical and periodontal parameters, and the expression of PPARG and other immune response-related genes. We examined 345 subjects with a healthy periodontium and without T2DM, 349 subjects with moderate or severe periodontitis but without T2DM, and 202 subjects with moderate or severe periodontitis and T2DM. PPARG SNPs rs12495364, rs1801282, rs1373640, and rs1151999 were investigated. Multiple logistic regressions adjusted for age, sex, and smoking status showed that individuals carrying rs1151999-GG had a 64% lower chance of developing periodontitis together with T2DM. The CCGT haplotype increased the risk of developing periodontitis together with T2DM. The rs1151999-GG and rs12495364-TC were associated with reduced risk of obesity, periodontitis, elevated triglycerides, and elevated glycated hemoglobin, but there was no association with gene expression. Polymorphisms of the PPARG gene were associated with developing periodontitis together with T2DM, and with obesity, lipid, glycemic, and periodontal characteristics.

Prevalence and associated factors of myofascial pain in orthognathic patients with skeletal class II malocclusion

Orthognathic patients with skeletal class II malocclusion frequently suffer from myofascial pain (MP).

PURPOSE

This study aimed to evaluate the prevalence and associated factors of MP in these patients.

METHODS

This cross-sectional study was performed in adult patients with skeletal Class II malocclusion requiring orthognathic surgery. They were divided according to the presence or absence of MP. The predictor variables were craniofacial morphology, sex, temporomandibular disorders, chronic pain, depression, and polymorphisms of dopamine receptors DRD2 (rs6275 and rs6276) and ANKK1 (rs1800497) genes. Data were submitted to statistical analyses using the linear regression model and Poisson regression with a significance level of 0.05.

RESULTS

Sixty-five individuals were selected, of which 50 (76.92%) were females. A total of 21 (32.3%) patients had MP. Individuals with MP showed a decrease in the mandible gonial angle (p = 0.042) and an increased risk of having temporomandibular joint (TMJ) disc displacement (p = 0.003), TMJ pain (p = 0.030), chronic pain (p = 0.001), and severe depression (p = 0.015). Additionally, individuals carrying AA and AG genotypes in rs6275, and CC genotype in rs6276, were more likely to have MP (p < 0.05).

CONCLUSION

In this study, 32.3% of skeletal class II orthognathic patients had MP, which was associated with a decreased gonial angle, TMJ disc displacement, TMJ pain, chronic pain, depression, and polymorphisms in the DRD2 gene.

Genetic polymorphisms are involved in oral health-related quality of life in skeletal class III patients submitted to orthognathic surgery

OBJECTIVE

This study aimed to evaluate whether sex and genetic polymorphisms impact the oral health-related quality of life (OHRQoL) preoperatively and the difference between preoperative and postoperative OHRQoL in skeletal Class III patients submitted to orthognathic surgery.

MATERIALS AND METHODS

This longitudinal study consisted of ninety-nine patients with skeletal Class III malocclusion who required orthognathic surgery. The Oral Health Impact Profile-14 (OHIP-14) is a questionnaire used to assess the OHRQoL with a 5-point Likert-type scale, covering seven domains related to physical and psychosocial factors. The questionnaire was applied in the preoperative and postoperative periods, and the difference scores were calculated to assess the OHRQoL after orthognathic surgery. The DNA was extracted from oral mucosa cells to evaluate genetic polymorphisms in ANKK1, DRD2, ESR1, and ESR2 through real-time PCR.

RESULTS

There was an improvement in all OHRQoL domains following orthognathic surgery (p < 0.05). In the preoperative evaluation, women presented worse OHRQoL (p < 0.05) than men. There was no statistical difference between sex and the OHRQoL after surgery (p > 0.05). When evaluating the polymorphisms and preoperative OHIP-14 scores, CT genotype patients for rs1800497 (ANKK1) had a worse perception of the physical pain domain than CC genotype (p = 0.026), and CC genotype patients for rs1256049 (ESR2) had a worse perception of the functional limitation domain than CT genotype (p = 0.002). In the analysis between polymorphisms and postoperative and preoperative difference scores, CT genotype patients for rs1256049 (ESR2) had a greater improvement in the perception of the physical pain domain than the CC genotype (p = 0.031). In rs6275 and rs6276 (DRD2), patients with the CC genotype worsened the perception of the functional limitation domain than the TT genotype (p = 0.045), and AA genotype patients worsened the perception of the functional limitation domain than GG genotype (p = 0.048) after surgery, respectively. In addition, patients with the CT genotype for rs1800497 (ANKK1) had a greater improvement of OHRQoL perception in the total scale than the TT genotype (p = 0.018), and CT genotype patients had a greater improvement in the perception of function limitation domain than TT genotype (p = 0.017).

CONCLUSION

Women have a worse perception of OHRQoL in the preoperative period of orthognathic surgery. Furthermore, polymorphisms in the ANKK1, DRD2, and ESR2 genes could be involved with OHRQoL in the preoperative period and following orthognathic surgery.

CLINICAL RELEVANCE

The knowledge of the genetic background concerning OHRQoL in skeletal class III patients would aid in clinical practice to screen for associated genetic factors and prevent OHRQoL deterioration, especially after orthognathic surgery, considering that patients' genetic profiles would soon be available.

IL17A and IL17RA gene polymorphisms in Fanconi anemia

Fanconi anemia is a rare autosomal recessive disease. In this disease, cytokine pathways can induce the bone marrow failure that is observed in individuals with Fanconi anemia. Interleukin IL-17 exhibits a protective effect in organisms because it induces neutrophil recruitment and shows a pathological role in several models of autoimmune diseases, periodontal disease, cancer, allograft rejection, and graft versus host disease. Polymorphisms in the IL17A and IL17RA genes were evaluated from DNA in saliva, comparing individuals with or without Fanconi anemia, using models of genotypic transmission (additive, dominant, and recessive). Polymorphisms in the IL17A and IL17RA genes (rs2241044 [C allele], rs879577 [C allele], rs9606615 [T allele], and rs2241043 [C allele]) were risk factors for developing Fanconi anemia. We also performed an analysis of gene markers with clinical variables in the Fanconi group. Polymorphisms in the IL17A gene (rs3819025 [A allele] and rs2275913 [G allele], respectively) were associated with an age of less than 20 years (p = 0.026; RP 0.65) and the female sex (p = 0.043; RP 0.88). The IL17RA gene was also associated with age and the presence of leukoplakia (a potentially malignant oral disorder). An age of less than 20 years was associated with rs917864 (T allele; p = 0.036; RP 0.67). The presence of leukoplakia was associated with rs17606615 (T allele; p = 0.042; RP 0.47). To our knowledge, this is the first study that associates IL17A and IL17RA gene polymorphisms with Fanconi anemia and examines rs2241044 polymorphisms in scientific literature thus far.

The role of IL17 and IL17RA polymorphisms in lethal pandemic acute viral pneumonia (Influenza A virus H1N1 subtype)

Background

The cytokines play an essential role in acute inflammatory processes, and the IL-17 may be responsible for ambiguous aspects, and the correlation with genetic polymorphisms could improve the search for this critical biomarker. Thus, this study aimed to evaluate the IL-17A and IL-17RA tissue expression and the polymorphisms that codified these proteins in a population that died of pandemic Influenza A virus H1N1 subtype compared to a non-pandemic Influenza virus population.

Methods

Necropsy lung samples immunohistochemistry was performed to assess the presence of IL-17A and IL-17RA in the pulmonary tissue. Eight single nucleotide polymorphisms were genotyped using TaqMan® technology.

Results

The Influenza A H1N1 pandemic group had higher tissue expression of IL-17A, higher neutrophil recruitment and shorter survival time between admission and death. Three single nucleotide polymorphisms conferred risk for pandemic influenza A H1N1, the AA genotype of rs3819025 G/A, the CC genotype of rs2241044 A/C, and the TT genotype of rs 2,241,043 C/T.

Conclusions

One IL17A polymorphism (rs381905) and two IL17RA polymorphisms (rs2241044 and rs2241043) represented biomarkers of worse prognosis in the population infected with pandemic influenza A H1N1. The greater tissue expression of IL-17A shows a Th17 polarization and highlights the aggressiveness of the pandemic influenza virus with its duality in the protection and pathogenesis of the pulmonary infectious process.

Novel mutations in GJA1 in two Brazilian families with oculodentodigital dysplasia

Oculodentodigital dysplasia (ODDD; MIM #164200), a rare genetic disorder characterized by abnormal craniofacial, dental, ocular, and digital features, is caused by mutations in GJA1 (gap junction alpha-1) gene and inherited in an autosomal dominant pattern. However, an autosomal recessive pattern is also reported. Here we described 2 families with members affected by ODDD. In the first family, the c.752G>C (p.S251T) and c.848C>T (p.P283L) heterozygous missense mutations and the c.825C>T (p.T275T) silent mutation were identified in the proband, which showed mild ODDD phenotypes, and in his mother, which displayed hemolytic anemia and thrombocytopenia. In the second family, the patients displayed typical features of ODDD, and Sanger sequencing identified a novel homozygous c.604C>T (p.R202C) missense mutation, whereas the parents carried the mutation. Together, these findings suggest that homozygous mutation in GJA1 induces a more severe ODDD phenotype, though interfamilial phenotype variability was observed, whereas compound heterozygous mutations in GJA1 cause a mild phenotype.

Brazilian Multiethnic Association Study of Genetic Variant Interactions among FOS, CASP8, MMP2 and CRISPLD2 in the Risk of Nonsyndromic Cleft Lip with or without Cleft Palate

Associations of CRISPLD2 (cysteine-rich secretory protein LCCL domain containing 2) and genes belonging to its activation pathway, including FOS (Fos proto-oncogene), CASP8 (caspase 8) and MMP2 (matrix metalloproteinase 2), with nonsyndromic orofacial cleft risk, have been reported, but the results are yet unclear. The aim of this study was to evaluate single nucleotide polymorphisms (SNPs) in FOS, CASP8 and MMP2 and to determine their SNP-SNP interactions with CRISPLD2 variants in the risk of nonsyndromic cleft lip with or without cleft palate (NSCL±P) in the Brazilian population. The SNPs rs1046117 (FOS), rs3769825 (CASP8) and rs243836 (MMP2) were genotyped using TaqMan allelic discrimination assays in a case-control sample containing 801 NSCL±P patients (233 nonsyndromic cleft lip only (NSCLO) and 568 nonsyndromic cleft lip and palate (NSCLP)) and 881 healthy controls via logistic regression analysis adjusted for the effects of sex and genomic ancestry proportions with a multiple comparison p value set at ≤0.01. SNP-SNP interactions with rs1546124, rs8061351, rs2326398 and rs4783099 in CRISPLD2 were performed with the model-based multifactor dimensionality reduction test complemented with a 1000 permutation-based strategy. Although the association between FOS rs1046117 and risk of NSCL±P reached only nominal p values, NSCLO risk was significantly higher in carriers of the FOS rs1046117 C allele (OR: 1.28, 95% CI: 1.10-1.64, p = 0.004), TC heterozygous genotype (OR: 1.59, 95% CI: 1.16-2.18, p = 0.003), and in the dominant model (OR: 1.50, 95% CI: 1.10-2.02, p = 0.007). Individually, no significant associations between cleft risk and the SNPs in CASP8 and MMP2 were observed. SNP-SNP interactions involving CRISPLD2 variants and rs1046117 (FOS), rs3769825 (CASP8) and rs243836 (MMP2) yielded several significant p values, mostly driven by FOS rs1046117 and CASP8 rs3769825 in NSCL±P, FOS rs1046117 in NSCLO and CRISPLD2 rs8061351 in NSCLP. Our study is the first in the Brazilian population to reveal the association of FOS rs1046117 with NSCLO risk, and to support that CRISPLD2, CASP8, FOS and MMP2 interactions may be related to the pathogenesis of this common craniofacial malformation.

Pain perception genes, asthma, and oral health: A reverse genetics study

Pain is an experience of a subjective nature, interpreted in a personal way and according to an extensive palette of factors unique to each individual. Orofacial pain can be acute or chronic and it is usually the main reason for the patient to seek dental care. Pain perception varies widely among individuals. This variability is considered a mosaic of factors, which include biopsychosocial factors and genetic factors. Understanding these differences can be extremely beneficial for pain management in a personalized and more efficient way. We performed association studies to investigate phenotypes associated with genetic markers in pain-related genes in two groups of patients who received more or less anesthesia during dental treatment. The study group was comprised of 1289 individuals participating in the Dental Registry and DNA Repository Project (DRDR) of the University of Pittsburgh, with 900 participants in the group that received the most anesthesia and 389 constituting the comparison group that received less anesthesia. We tested 58 phenotypes and genotypic data of seven SNPs in genes that are associated with pain perception, pain modulation and response to drugs used in pain treatment: COMT (rs4818 and rs6269), GCH1 (rs3783641), DRD2 (rs6276), OPRM1 (rs1799971), SCN9A (rs6746030) and SCN10A (rs6795970). The analysis revealed a protective effect of rs1799971 on asthma in the total sample. rs3783641 was associated with salivary secretion disorders in females who received more anesthesia. rs1799971 was also associated with periodontitis in Whites who received less anesthesia. rs4818 was associated with disease and other tongue conditions in the group composed of Blacks who received less anesthesia. In conclusion, our study implicated variants in pain-related genes in asthma and oral phenotypes.

Genetic polymorphisms and their effects on the severity of silicosis in workers exposed to silica in Brazil

Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by inhalation of silica particles. Genetic factors might play a role in the severity silicosis. We sought to evaluate the influence of polymorphisms in the ACE, FAS, FASLG, NOS2, IL1RN, FAM13A, TGFB1, and TNF genes on the severity of silicosis. Methods: Nine polymorphisms were genotyped by PCR in a sample of 143 patients with silicosis in the state of Rio de Janeiro, Brazil. Results: Fifty-seven patients (40%) were classified as having simple silicosis and 86 (60%) were classified as having complicated silicosis. The TT genotype of rs1800469 in the TGFB1 gene showed a protective effect for complicated silicosis (OR = 0.35; 95% CI, 0.14-0.92; p = 0.028) when compared with the other two genotypes (CC+CT). The polymorphic T allele of rs763110 in the FASLG gene (OR = 0.56; 95% CI, 0.31-0.99; p = 0.047), as well as a dominant model for the T allele (TT+CT: OR = 0.37; 95% CI, 0.15-0.96; p = 0.037), also showed a protective effect. When patients with simple silicosis despite having been exposed to silica for a longer time (> 44,229 hours) were compared with patients with complicated silicosis despite having been exposed to silica for a shorter time, the T allele of rs763110 in the FASLG gene (OR = 0.20; 95% CI, 0.08-0.48; p < 0.0001), as well as dominant and recessive models (OR = 0.06; 95% CI, 0.00-0.49; p = 0.01 and OR = 0.22; 95% CI, 0.06-0.77; p = 0.014, respectively), showed a protective effect against the severity of silicosis. Conclusions: It appears that rs1800469 polymorphisms in the TGFB1 gene and rs763110 polymorphisms in the FASLG gene are involved in the severity of silicosis. Given the lack of studies relating genetic polymorphisms to the severity of silicosis, these results should be replicated in other populations.

Genetic contribution to cancer risk in patients with tooth loss: a genetic association study

Early-stage cancer diagnosis is critical for higher survival rates. Because early cancers can be difficult to detect, our focus is on the identification of cancer risk markers such as pleiotropic genes involved in the etiology of both craniofacial conditions and cancers. In this study we aimed to test if our previously detected association between ERN1 rs196929 marker and oral health outcomes would be detected in individuals diagnosed with cancer as well as in a subpopulation of individuals who also had one or more teeth missing due to dental caries, periodontal disease, or periapical lesions. We genotyped a total of 1,671 subjects and selected a subset of 1,421 subjects for stratified analysis of cancer types; three hundred and twelve self-reported a diagnosis of various cancer types and 1,109 reported never receiving a diagnosis of cancer. Our results showed a statistically significant association between the rs196929 in ERN1, and cancer overall in both the additive and dominant models (OR = 1.37, 95% C.I. 1.06-1.79, p = 0.014). When we stratified the analysis for each cancer type, our results show that the rs196929 ERN1 variant is associated with skin cancer (OR = 2.07, 95% C.I. 1.27-3.37, p = 0.003) and breast cancer (OR = 1.83, 95% C.I. 1.13-2.99, p = 0.013) in the subset of patients that had tooth loss. An additional nominal association between the rs196929 in ERN1 and male's reproductive system cancers (OR = 1.96, 95% C.I. 1.07-3.59, p = 0.028) was identified. We hope that our study helps guide future genetic studies on these cancers and this specific genetic variant as well as drive attention to the potential for oral health outcomes to serve as indicators for cancer risk. The early identification of genetic markers and/or oral conditions that indicate increased cancer risk could positively impact cancer outcomes and survival rates with timely implementation of preventive and diagnostic measures. In conclusion, our results suggest that the genetic variant in ERN1 (rs196929) is associated with increased risk of skin and breast cancers.

Evaluating Time-Dependent Extraction of Exfoliated Oral Mucosal Cells from Used Toothbrushes and Miswak

An integral part of forensic work is DNA quantification and profiling, which necessitates many highquality samples for good results. Oral mucosal cells have become an essential source of genomic DNA in epidemiological studies. The time of collecting DNA samples is a critical factor in forensic science. To compares the time-dependent extraction of DNA yield and purity from exfoliated oral epithelial cells from toothbrushes and miswak used for time intervals up to 5 months. Thirty healthy volunteers were given toothbrushes and miswak to use for six days. The used toothbrushes and miswak were collected, stored at room temperature, and analyzed immediately and at the end of the first, second, third, fourth, and fifth months. Comparisons between the two independent groups of toothbrush and miswak were done by an independent two-sample t-test. The changes over time for each outcome were analyzed using repeated-measures ANOVA. DNA yield of the exfoliated oral epithelial cell samples was higher from female samples, while DNA purity was higher in the male samples. The Miswak contained a sufficient amount of DNA similar to toothbrushes. The yield and purity are not significantly altered by storing them for at least five months at room temperature.

Association of the estrogen receptor gene with oral health-related quality of life in patients with dentofacial deformities

This study aimed to evaluate the associations between oral health-related quality of life (OHRQoL) and patient-associated factors and polymorphisms in the estrogen receptor 1 (ESR1) and 2 (ESR2) genes in patients with dentofacial deformities (DFD). This cross-sectional study included 234 adult individuals. Data such as age, sex, and the type of facial profile (I, II, or III), were collected, and the short-form oral health impact profile 14 (OHIP-14) questionnaire was used to assess their OHRQoL. DNA was collected from oral mucosa cells, and the polymorphisms in ESR1 (rs2234693 and rs9340799) and ESR2 (rs1256049 and rs4986938) were evaluated using real-time polymerase chain reaction. The data were subjected to statistical analysis at a significance level of 5%. Individuals over 28 years of age exhibited worse OHRQoL (p = 0.003) than individuals aged less than or equal to 28 years. Women had worse OHRQoL than men (p < 0.001). Profile II individuals had worse OHRQoL in the social disability domain than profile III individuals (p = 0.030). Genetic analysis showed that rs9340799 was associated with OHRQoL in the functional limitation domain, and GG individuals exhibited worse OHRQoL than individuals carrying the AA/AG genotypes (p < 0.030). In the social handicap domain, individuals with GG genotype in rs9340799 exhibited worse OHRQoL than AG individuals (p < 0.043). Collectively, our results reveal that factors including age, sex, and type of facial profile, are associated with OHRQoL in patients with DFD. In addition, individuals with the GG genotype in rs9340799 (ESR1) may experience a negative impact on OHRQoL in the functional limitation and social handicap domains.

Analysis of GLT6D1 and CDKN2BAS gene polymorphisms in Brazilian patients with advanced periodontitis

Gene polymorphisms can predispose to periodontal disease, as demonstrated by the well-documented association between aggressive periodontitis and single nucleotide polymorphisms (SNPs) such as rs153745 in the GLT6D1 gene and rs3217992 in the CDKN2BAS gene. The purpose of this study was to evaluate the presence of these SNPs in Brazilian patients with advanced periodontitis (stages III/IV, Grade B/C) vs. healthy controls. A total of 100 patients with periodontitis (Group BC) were enrolled. Of these, 51 patients were classified as stage III and 49 patients were classified as stage IV, and 52 were Grade B (Group B) and 48 were Grade C (Group C). The control Group consisted of 61 healthy subjects. DNA samples extracted from buccal epithelial cells were used to genotype the SNPs rs1537415 (GLT6D1) and rs3217992 (CDKN2BAS) by real-time quantitative PCR. No significant differences in polymorphism frequency were found between the control Group and each of the patient groups (BC, B, or C), and Group B did not differ from Group C. In conclusion, the evaluated SNPs had no significant influence on the prevalence of periodontal disease in the sampled Brazilian population.

DNMT3B (rs2424913) polymorphism is associated with systemic lupus erythematosus alone and with co-existing periodontitis in a Brazilian population

The association between Periodontitis and Systemic Lupus Erythematosus (SLE) has been primarily based on their similar pathophysiology and both are associated with genetic polymorphisms.

OBJECTIVES

To investigate an association between the methylation-related gene polymorphisms DNMT3B (rs2424913) and MTHFR (rs1801133) to Systemic Lupus Erythematosus (SLE) and Periodontitis.

METHODOLOGY

In total, 196 individuals of all genders aged 24 to 60 years old were allocated into four groups based on their systemic and periodontal status, namely: Healthy control (n=60), periodontitis (n=51), SLE (n=47), and SLE + periodontitis (n=38). Individuals with SLE were stratified according to disease activity (SLEDAI) in inactive or active. We performed polymorphism analysis using PCR-RFLP with genomic DNA from mouthwash. We analyzed data using Fisher's Exact, Chi-square test, and regression models.

RESULTS

Periodontal status were similar in subjects with periodontitis alone and combined with SLE. SLE patients with periodontitis had a longer SLE diagnosis than SLE only (p=0.001). For DNMT3 B polymorphism, the periodontitis, SLE, and Inactive SLE + periodontitis groups showed a higher frequency of T allele and TT genotypes compared to healthy controls (p<0.05). Regression analyses showed that the TT genotype is a strong risk factor for periodontitis (OR=4.53; CI95%=1.13-18.05) and also for SLE without periodontitis (OR=11.57; CI95%=3.12-42.84) and SLE with periodontitis (OR=5.27; CI95%=1.25-22.11) when compared to control.

CONCLUSION

SLE patients with periodontitis had a longer length of SLE diagnosis. The DNMT3B (rs2424913) polymorphism was associated with periodontitis and SLE alone or combined with periodontitis. Our study contributes to understanding the genetic mechanisms involved in periodontitis and SLE susceptibility.

Do boys with MAOA_LPR*2R allele present cognitive and learning impairments?

Monoamine oxidase A (MAOA) polymorphisms have been associated with antisocial disorders. Less attention has been paid to the cognitive functioning of individuals with different MAOA alleles. No study has described the cognitive phenotype associated with the less frequent, low enzyme activity allele, MAOA_LPR*2R.

Regulation of oxytocin receptor gene expression in obsessive-compulsive disorder: a possible role for the microbiota-host epigenetic axis

BACKGROUND

Obsessive-compulsive disorder (OCD) is a prevalent and severe clinical condition. Robust evidence suggests a gene-environment interplay in its etiopathogenesis, yet the underlying molecular clues remain only partially understood. In order to further deepen our understanding of OCD, it is essential to ascertain how genes interact with environmental risk factors, a cross-talk that is thought to be mediated by epigenetic mechanisms. The human microbiota may be a key player, because bacterial metabolites can act as epigenetic modulators. We analyzed, in the blood and saliva of OCD subjects and healthy controls, the transcriptional regulation of the oxytocin receptor gene and, in saliva, also the different levels of major phyla. We also investigated the same molecular mechanisms in specific brain regions of socially isolated rats showing stereotyped behaviors reminiscent of OCD as well as short chain fatty acid levels in the feces of rats.

RESULTS

Higher levels of oxytocin receptor gene DNA methylation, inversely correlated with gene expression, were observed in the blood as well as saliva of OCD subjects when compared to controls. Moreover, Actinobacteria also resulted higher in OCD and directly correlated with oxytocin receptor gene epigenetic alterations. The same pattern of changes was present in the prefrontal cortex of socially-isolated rats, where also altered levels of fecal butyrate were observed at the beginning of the isolation procedure.

CONCLUSIONS

This is the first demonstration of an interplay between microbiota modulation and epigenetic regulation of gene expression in OCD, opening new avenues for the understanding of disease trajectories and for the development of new therapeutic strategies.

Genetic polymorphisms of genes involved in oxidative stress and inflammatory management in oncopediatric patients with chemo-induced oral mucositis

Oral mucositis (OM) is a painful inflammatory oral condition that affects children who undergo chemotherapy. Oxidative stress is a known OM mediator and pro-inflammatory cytokines contribute to the amplification of the immune response.

FTO and ADRB2 Genetic Polymorphisms Are Risk Factors for Earlier Excessive Gestational Weight Gain in Pregnant Women with Pregestational Diabetes Mellitus: Results of a Randomized Nutrigenetic Trial

Excessive gestational weight gain (GWG) is associated with increased risk of maternal and neonatal complications. We investigated obesity-related polymorphisms in the FTO gene (rs9939609, rs17817449) and ADRB2 (rs1042713, rs1042714) as candidate risk factors concerning excessive GWG in pregnant women with pregestational diabetes. This nutrigenetic trial, conducted in Brazil, randomly assigned 70 pregnant women to one of the groups: traditional diet (n = 41) or DASH diet (n = 29). Excessive GWG was the total weight gain above the upper limit of the recommendation, according to the Institute of Medicine guidelines. Genotyping was performed using real-time PCR. Time-to-event analysis was performed to investigate risk factors for progression to excessive GWG. Regardless the type of diet, AT carriers of rs9939609 (FTO) and AA carriers of rs1042713 (ADRB2) had higher risk of earlier exceeding GWG compared to TT (aHR 2.44; CI 95% 1.03-5.78; p = 0.04) and GG (aHR 3.91; CI 95% 1.12-13.70; p = 0.03) genotypes, respectively, as the AG carriers for FTO haplotype rs9939609:rs17817449 compared to TT carriers (aHR 1.79; CI 95% 1.04-3.06; p = 0.02).

Evaluation of genome-wide association signals for nonsyndromic cleft lip with or without cleft palate in a multiethnic Brazilian population

OBJECTIVE

To evaluate previous nonsyndromic cleft lip with or without cleft palate (NSCL±P) associated signals in 4p16.2, 8p11.23, 12q13.13, 12q13.2 and 17q21.32 in a multiethnic Brazilian cohort.

DESIGN

The single nucleotide polymorphisms (SNPs) rs34246903 in 4p16.2, rs13317 in 8p11.23 (FGFR1, fibroblast growth factor receptor 1), rs3741442 in 12q13.13, rs705704 in 12q13.2 and rs4968247 in 17q21.32 were genotyped with TaqMan allelic discrimination assays in a case-control sample including 801 NSCL±P patients [233 nonsyndromic cleft lip (NSCLO) and 568 nonsyndromic cleft lip and palate (NSCLP)] and 881 healthy controls. Multiple logistic regression analyses, considering sex and genomic ancestry as covariates, were conducted, and the p value was adjusted with Bonferroni multiple correction testing (p ≤ 0.01).

RESULTS

Although several associations were identified, those that resisted the multiple correction testing involved the alleles and genotypes of rs34246903 and rs13317. The NSCLO group had a lower frequency of the minor C allele of rs34246903 compared to controls, giving an odds ratio (OR) of 0.74 [95% confidence interval (CI): 0.59-0.93, p = 0.01]. The rs34246903 CC genotype (homozygous) and the recessive model revealed significant protective associations with NSCLO, yielding ORs of 0.50 (95% CI: 0.29-0.85, p = 0.005) and 0.55 (95% CI: 0.33-0.93, p = 0.01) respectively. The presence of C variant allele of rs13317 (OR: 0.81, 95% CI: 0.69-0.96, p = 0.01) as well the TC genotype (OR: 0.77, 95% CI: 0.62-0.94, p = 0.01) and the dominant model (OR: 0.77, 95% CI: 0.63-0.94, p = 0.009) showed significant associations with reduced risk of NSCL±P.

CONCLUSION

Our study is the first to support the association of rs34246903 (4p16.2) with NSCLO and rs13317 within FGFR1 with NSCL±P in the highly admixed Brazilian population. Further studies are needed to determine the functionality of those SNPs or to identify the causal markers in linkage disequilibrium with those susceptibility markers.

Influence of clinical factors, IL4 and IL6 genes polymorphisms in functional healing in late replantation

Abstract To investigate the genetic association in a sample of replanted teeth, it is necessary to observe the extreme phenotypes, such as, teeth that underwent functional healing and those extracted due to severe external root resorption. Thus, this study aimed to investigate the association of age of the patients, root development, storage media, and polymorphisms in the interleukin 4 (IL4) and interleukin 6 (IL6) genes with teeth that presented extreme outcomes, as functional healing or extraction, in a group whose replantation techniques did not follow the International Association of Dental Traumatology (IADT) 2012 guidelines. Forty-three avulsed and replanted teeth that did not follow IADT 2012 guidelines and underwent functional healing or were extracted were included. Periapical radiographs employed for this study were taken soon after tooth replantation and after 1 year. For genotypic IL4 and IL6 genes analysis, DNA of oral mucosa cells was extracted. Real-time- PCR performed for genotyping polymorphisms in IL4 and IL6 genes. Clinical and genetic variables were analyzed by the Chi-square test and the “Z” test. P values < .05 were considered significant. The results showed that functional healing and extraction were associated with storage media and with the rs2243268 of IL- 4 gene polymorphisms. As conclusion, the C rs2243268 allele of IL4 gene may have a positive relationship with functional healing teeth that were replanted not following the 2012 IADT guidelines. Keeping the tooth dry is associated to a fast loss of avulsed and replanted teeth after 1-year follow-up.

Contrasting maternal and paternal genetic histories among five ethnic groups from Khyber Pakhtunkhwa, Pakistan

Northwest Pakistan has served as a point of entry to South Asia for different populations since ancient times. However, relatively little is known about the population genetic history of the people residing within this region. To better understand human dispersal in the region within the broader history of the subcontinent, we analyzed mtDNA diversity in 659 and Y-chromosome diversity in 678 individuals, respectively, from five ethnic groups (Gujars, Jadoons, Syeds, Tanolis and Yousafzais), from Swabi and Buner Districts, Khyber Pakhtunkhwa Province, Pakistan. The mtDNAs of all individuals were subject to control region sequencing and SNP genotyping, while Y-chromosomes were analyzed using 54 SNPs and 19 STR loci. The majority of the mtDNAs belonged to West Eurasian haplogroups, with the rest belonging to either South or East Asian lineages. Four of the five Pakistani populations (Gujars, Jadoons, Syeds, Yousafzais) possessed strong maternal genetic affinities with other Pakistani and Central Asian populations, whereas one (Tanolis) did not. Four haplogroups (R1a, R1b, O3, L) among the 11 Y-chromosome lineages observed among these five ethnic groups contributed substantially to their paternal genetic makeup. Gujars, Syeds and Yousafzais showed strong paternal genetic affinities with other Pakistani and Central Asian populations, whereas Jadoons and Tanolis had close affinities with Turkmen populations from Central Asia and ethnic groups from northeast India. We evaluate these genetic data in the context of historical and archeological evidence to test different hypotheses concerning their origins and biological relationships.

THE POLYMORPHISM OF METALLOPROTEINASES 1 AND 13 AND POSTTRAUMATIC ELBOW STIFFNESS

Introduction

To evaluate the relationship between the genetic polymorphism of matrix metalloproteinases 1 and 13 and posttraumatic elbow stiffness, as well as the association of other risk factors with this condition.

Materials and methods

We evaluated 20 patients with posttraumatic elbow stiffness and 12 controls with traumatic elbow disorders without contracture. Deoxyribonucleic acid (DNA) was obtained from buccal mucosa epithelial cells of the volunteers. The MMP-1 and MMP-13 genotypes were determined using PCR-restriction fragment length polymorphism assays.

Results

We did not find any significant differences in the frequency of genotypes and alleles between the test and control groups for the polymorphism of metalloproteinases 1 and 13. We observed that genotypes 1G/2G and 2G/2G of MMP-1 were present in 65% (13/20) of patients with articular stiffness and 50% (6/12) of controls (p = 0.599). Genotypes A/A and A/G of MMP-13 were obtained in 95% (19/20) of patients and 91.6% (11/12) of controls (p = 0.491). Among the prognostic factors for elbow stiffness, only immobilization time correlated positively. The mean immobilization time for cases and controls were 16 ± 10 days and 7 ± 7 days, respectively (p = 0.017).

Conclusion

The genetic polymorphism of MMP-1 at position -1607 and MMP-13 at position -77 was not associated with post-traumatic elbow stiffness. Level of Evidence III; Prognosis Study; Case-Control Study.

Analysis of mutations in leu tRNA gene in patients of heart diseases

Cardiovascular diseases (CVD) are the leading cause of death all over the world. Beside general risk factors, there are some genetic factors which lead to cardiovascular diseases. Various nuclear DNA mutation and also mitochondrial DNA mutations have been related with cardiovascular diseases. In the present study, a total of 21 samples were collected from different families residing in district Dir. DNA was extracted from buccal epithelial cells using saliva. The mitochondrial tRNA leu (MT TL1) gene was amplified by PCR and 10 samples of different families were sequenced. The sequence was aligned with revised Cambridge Reference Sequence (rCRS) accession # NC-012920.1. It is concluded that cardiovascular diseases in our subjects are not due to mutation in the mitochondrial leucine tRNA gene. However, a large population of subjects with cardiovascular diseases needs to be studied and whole mitochondrial DNA is needed to be sequenced in the subjects with CVD. This will give an idea about the probable DNA marker which can be used to prevent loses due to these diseases at a very early stages.

In Search for Biomarkers in Obsessive-Compulsive Disorder: New Evidence on Saliva as a Practical Source of DNA to Assess Epigenetic Regulation

BACKGROUND

Brain-Derived Neurotrophic Factor (BDNF) is a promising candidate biomarker in both the development and aetiology of different neuropsychiatric conditions, including obsessive-compulsive disorder (OCD). Most of the studies in the field have been carried out in blood cells, including peripheral blood mononucleated cells (PBMCs), although DNA of high quality can be easily isolated from saliva.

OBJECTIVE

The objective of this study was to evaluate the epigenetic regulation of the BDNF gene in the saliva of a clinical sample of OCD patients in order to assess this source as an alternative to blood.

METHODS

We first analyzed DNA methylation levels at BDNF in the saliva of subjects suffering from OCD (n= 50) and healthy controls (n=50). Then, we compared these data with the results previously obtained for the same genomic region in blood samples from the same patients and controls (CTRL).

RESULTS

Our preliminary data showed a significant reduction of 5mC levels at BDNF gene (OCD: 1.23 ± 0.45; CTRL: 1.85 ± 0.64; p < 0.0001) and a significant correlation between DNA methylation in PBMCs and saliva (Spearman r = 0.2788).

CONCLUSION

We support the perspective that saliva could be a possible, reliable source, and a substitute for blood, in search of epigenetic biomarkers in OCD.

Is there an association of genetic polymorphisms of the catechol-O-methyltransferase gene (rs165656 and rs174675) and the 5-hydroxytryptamine receptor 2A gene (rs4941573 and rs6313) with sleep bruxism in individuals with obstructive sleep apnea?

OBJECTIVE

To evaluate the association of single-nucleotide polymorphisms within the catechol-O-methyltransferase and 5-hydroxytryptamine receptor 2A genes with sleep bruxism in individuals diagnosed with obstructive sleep apnea.

DESIGN

Sixty-nine individuals with suspected sleep-related problems were evaluated by polysomnography, following the recommendations of the American Academy of Sleep Medicine. Deoxyribonucleic acid (DNA) samples were collected only from 48 of the study participants because of missing polysomnographic data. DNA samples were collected and two single-nucleotide polymorphisms in the 5-hydroxytryptamine receptor 2A encoding HTR2A gene (rs4941573 and rs6313) and two in the catechol-O-methyltransferase gene (rs165656 and rs174675) were selected to be genotyped using real-time polymerase chain reaction. The association between sleep bruxism and genetic polymorphisms was investigated by recessive and dominant models. Association analyses were performed using a 95% confidence interval and the level of statistical significance was p < 0.05.

RESULTS

From the 69 study participants, 48 were included in the polymorphism analysis and sleep bruxism was present in 35.4%. No significant differences were observed in the dominant and recessive models (p > 0.05). Haplotype and diplotype analyses revealed the predicted four haplotypes and two diplotypes were not associated with sleep bruxism.

CONCLUSION

Polymorphisms rs174675 and rs165656 in the catechol-O-methyltransferase gene and rs4941573 and rs6313 in the 5-hydroxytryptamine receptor 2A gene were not significantly associated with sleep bruxism in individuals with obstructive sleep apnea.

Polymorphisms in Genes of Lipid Metabolism Are Associated with Type 2 Diabetes Mellitus and Periodontitis, as Comorbidities, and with the Subjects' Periodontal, Glycemic, and Lipid Profiles

BACKGROUND

Type 2 diabetes mellitus (T2DM) and periodontitis (P) commonly occur as comorbidities, but the commonalities in the genetic makeup of affected individuals is largely unknown. Since dyslipidemia is a frequent condition in these individuals, we investigate the association of genomic variations in genes involved in lipid metabolism with periodontal, glycemic, lipid profiles, and the association with periodontitis and T2DM (as comorbidities).

METHODS

Based on clinical periodontal examination and biochemical evaluation, 893 subjects were divided into T2DM+P (T2DM subjects also affected by periodontitis, n = 205), periodontitis (n = 345), and healthy (n = 343). Fourteen single-nucleotide polymorphisms (SNPs) were investigated: LDLR gene (rs5925 and rs688), APOB (rs676210, rs1042031, and rs693), ABCC8 (rs6544718 and 6544713), LPL (rs28524, rs3735964, and rs1370225), HNF1A (rs2650000), APOE (rs429358 and rs7412), and HNF4A (rs1800961). Multiple linear and logistic regressions (adjusted for covariates) were made for all populations and stratified by sex and smoking habits.

RESULTS

Individuals carrying APOB-rs1042031-CT (mainly women and never smokers) had a lower risk of developing periodontitis and T2DM (T2DM+P); altogether, this genotype was related with healthier glycemic, lipid, and periodontal parameters. Significant disease-phenotype associations with gene-sex interaction were also found for carriers of APOB-rs1676210-AG, HNF4A-rs1800961-CT, ABCC8-rs6544718-CT, LPL-rs13702-CC, and LPL-rs285-CT.

CONCLUSIONS

Polymorphisms in lipid metabolism genes are associated with susceptibility to T2DM-periodontitis comorbidities, demonstrating gene-sex interaction. The APOB-rs1042031 was the most relevant gene marker related to glucose and lipid metabolism profiles, as well as with obesity and periodontitis.

Genetic Polymorphisms of the TGFB1 Signal Peptide and Promoter Region: Role in Wilms Tumor Susceptibility?

The aim of the present study was to investigate the rs1800468 (G-800A), rs1800469 (C-509T), rs1800470 (C29T), and rs1800471 (G74C) TGFB1 genetic polymorphisms and their haplotype structures in patients with Wilms Tumor (WT) and neoplasia-free controls. The genomic DNA was extracted from 35 WT patients and 160 neoplasia-free children, and the TGFB1 polymorphisms were genotyped by polymerase chain reaction, followed by restriction fragment length polymorphism. The haplotype structures were inferred, and permutation and logistic regression tests were performed to check for differences in haplotype distribution between the control and WT individuals. Positive associations were found in the recessive model for rs1800469 T allele (OR: 8.417; 95% CI: 3.177 to 22.297; P < 0.001) and for the rs1800470 C allele (OR: 3.000; 95% CI: 1.296 to 6.944; P = 0.01). Haplotype analysis revealed a significant negative association between GCTG and WT (OR: 0.236, 95% CI: 0.105 to 0.534; P = 0.0002); by contrast, the GTTG haplotype was associated with increased risk for WT (OR: 12.0; 95% CI: 4.202 to 34.270; P < 0.001). Furthermore, rs1800469 was negatively correlated with tumor size and a trend toward a positive correlation for capsular invasion was observed in the dominant model (Tau-b: −0.43, P = 0.02 and tau-b: 0.5, P = 0.06, respectively). This is the first study with rs1800468, rs1800469, rs1800470, and rs1800471 TGFB1 polymorphisms in WT, and our results suggest that the TGFB1 promoter and signal peptide region polymorphisms may be associated with WT susceptibility and clinical presentation.

ABCG2 polymorphism, age and leukocyte count may contribute to oral mucositis in oncopediatric patients

The study investigated the relationship between genetic polymorphisms and the development of oral mucositis in pediatric patients undergoing chemotherapy involving methotrexate. A longitudinal study was conducted with 64 patients, and oral mucositis was evaluated by the modified Oral Assessment Guide, which aims to diagnose and classify oral mucositis. Epithelial cells were obtained by mouthwash and DNA was extracted. The polymorphisms MTHFR (rs1801133), DNMT3B (rs2424913), ABCC2 (rs717620), ABCG2 (rs2231137) and ABCG2 (rs2231142) were analyzed by PCR-RFLP method. Demographic, hematological and biochemical data were collected from medical records. Statistical analysis was performed using the SPSS software adopting a p-value of 0.05. Male sex predominated (56.2%), and the mean age was 10.8 years (± 4.9). Oral mucositis affected 65.6% of the patients, of which 61.9% developed the severe form of the disease. For the ABCG2 gene (rs2231142), the rare A allele and CA genotype were more frequent in individuals with mucositis (p= 0.02; RR = 0.60; CI = 0.387 - 0.813). The severity of the disease was mainly observed in younger patients (median = 9 years; p=0.02). Patients with severe oral mucositis presented lower leukocytes count (median = 2.150 mm3) compared to patients with the mild/moderate form (median = 4.200 mm3; p=0.03). Female patients and each 10,000-platelet increase were protective factors against the onset of oral mucositis (p=0.02). It is concluded that rs2231142 polymorphism increases the likelihood of oral mucositis and younger patients and patients with low leukocytes counts are more likely to develop severe form.

Occlusal problems, mental health issues and non-carious cervical lesions

Non-carious cervical lesions (NCCLs) are characterized by a loss of hard dental tissue near the cement-enamel junction with multifactorial etiology. The aim of this study was to demonstrate that occlusal factors as attrition, malocclusion, and bruxism, and mental disorders as depression, stress, and anxiety are involved in the etiology of NCCLs. Salivary samples and clinical data of 340 individuals selected from 6,112 participants were obtained from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository project. The affected group was formed by individuals with NCCL (34 females, 34 males, mean age 55.34 years). In addition, the comparison group was formed by individuals without NCCL (136 females, 136 males, mean age 55.14 years). Eleven single-nucleotide polymorphisms (SNPs) previously associated with mental disorders were genotyped and tested for association with NCCLs. When all occlusal factors were combined there was found a significant association with NCCL (p = 0.000001/adjusted OR 4.38, 95% CI 2.50-7.69). Attrition (OR 3.56, 95% CI 2.00-6.32) and malocclusion (OR 5.09, 95% CI 1.65-15.68) as separate variables showed statistically significant associations with NCCL. There was a significant difference in stress history between the two groups (OR 2.17, 95% CI 1.08-4.39). No associations between NCCLs and the SNPs selected were found. However, when the occlusal factors were analyzed as covariates, associations were found between bruxism and seven of the selected SNPs. Our results suggest that occlusal factors might be associated with NCCLs.

Forensic DNA profiling of tears stains from commonly encountered substrates

The detection and recovery of body fluid evidence to reconstruct the involvement of people in a crime is an essential step in forensic investigation. The presence of tears is extremely rare but widely misunderstood because of its nature of secretion and low volumes found. They may be secreted in cases of sexual crimes, kidnaping, and violence among many other emotionally disturbing scenarios. It is suggestive that tears are an excellent source of epithelial cells for DNA to establish identity. They are deposited on tissue paper or handkerchief and lesser common substrates include bedding, face mask, and balaclava. Trace or touch DNA can also be retrieved from used contact lenses. Since tears can be secreted due to an emotional response, they can attract forensic analysis for identification. DNA profiling from these substrates is promising in the absence of other commonly found body fluids such as blood or saliva. The current study was done to explore the use of fresh and aged tear samples for forensic DNA analysis from three different substrates i.e., tissue paper, cotton fabric, and contact lenses. STR profiles were successfully obtained from all sample types (n = 60) with 100% allele recovery. The analysis provided consistent evidence that DNA extracted using this methodology was helpful to get reliable DNA profiles for forensics comparable with that from blood or saliva for personal identification.

Mutations in the osteoprotegerin-encoding gene are associated with temporomandibular joint ankylosis

OBJECTIVE

This study aimed to investigate genetic variations in the osteoprotegerin-encoding gene (TNFRSF11B) in patients with temporomandibular joint ankylosis (TMJA).

STUDY DESIGN

The sample comprised 17 patients diagnosed with TMJA, of both sexes with ages ranging from 6 to 57 years old. TNFRSF11B mutational analysis was performed using the Sanger sequencing method with DNA extracted from oral cells, and the functional impact prediction of the variants was assessed using bioinformatic analysis.

RESULTS

Sequencing analysis identified 15 (88.23%) patients that presented at least 1 genetic variant in TNFRSF11B. The mutation rs202090603 (p.E33K) was found in 6 individuals, and rs140782326 (p.V281M), rs11573942 (p.L295), and rs1375250340 (p.I389T) were identified in 1 subject each. According to the pathogenicity potential of mutations, 3 variants were considered of low impact (rs2073618, rs202090603, and rs2228568) and 3 as disease causing (rs140782326, rs11573942, and rs1375250340). The variant rs202090603 (p.E33K) was found in the first cysteine domain with differences in the loop positions of p.E33K mutated the 3D structure of osteoprotegerin.

CONCLUSION

Two polymorphisms (rs2073618 and rs2228568) and the mutations rs202090603 (p.E33K), rs140782326 (p.V281M), rs11573942 (p.L295), and rs1375250340 (p.I389T) in the TNFRSF11B gene may be associated with TMJA.

PPARα Gene Is Involved in Body Composition Variation in Response to an Aerobic Training Program in Overweight/Obese

The objective of this study was to investigate the relationship of the polymorphism in Intron 7 G/C (rs 4253778) of the peroxisome proliferator-activated receptor alpha (PPARα) gene with the magnitude of changes in the body composition of an overweight and obese population that underwent an aerobic training program. Fifty-eight previously inactive men and women, body mass index (BMI) 31.5 ± 2.8 kg/m², 46.5% (n = 27) genotyped as CC genotype and 53.5% (n = 31) as CA+AA, underwent a 12-week aerobic training (walking/running). Aerobic capacity (ergospirometry), body composition (DXA), and nutritional assessment were made before and 48 h after the experimental protocol. Two-way ANOVA, chi-square test, and logistic regression were used (p < 0.05). Twenty-seven volunteers (46.5%) were identified as CC genotype and 31 (53.5%) as CA+AA genotype. Time-group interaction showed that there was no difference in these between two allele groups. However, differences in distribution of respondents or nonresponders according to allele A were identified for fat mass (p ≤ 0.003), percentage fat mass (p ≤ 0.002), the waist (p ≤ 0.009), abdomen (p ≤ 0.000), and hip (p ≤ 0.001), this difference being independent for the fat mass. Meanwhile, sex, age, and nutritional management have also been found to be influential factors. It is concluded that the PPARα gene is involved in varying body composition in response to an aerobic training program.

Identification of Novel Variants in Cleft Palate-Associated Genes in Brazilian Patients With Non-syndromic Cleft Palate Only

The identification of genetic risk factors for non-syndromic oral clefts is of great importance for better understanding the biological processes related to this heterogeneous and complex group of diseases. Herein we applied whole-exome sequencing to identify potential variants related to non-syndromic cleft palate only (NSCPO) in the multiethnic Brazilian population. Thirty NSCPO samples and 30 sex- and genetic ancestry-matched healthy controls were pooled (3 pools with 10 samples for each group) and subjected to whole-exome sequencing. After filtering, the functional affects, individually and through interactions, of the selected variants and genes were assessed by bioinformatic analyses. As a group, 399 variants in 216 genes related to palatogenesis/cleft palate, corresponding to 6.43%, were exclusively identified in the NSCPO pools. Among those genes are 99 associated with syndromes displaying cleft palate in their clinical spectrum and 92 previously related to cleft lip palate. The most significantly biological processes and pathways overrepresented in the NSCPO-identified genes were associated with the folic acid metabolism, highlighting the interaction between LDL receptor-related protein 6 (LRP6) and 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) that interconnect two large networks. This study yields novel data on characterization of specific variants and complex processes and pathways related to NSCPO, including many variants in genes of the folate/homocysteine pathway, and confirms that variants in genes related to syndromic cleft palate and cleft lip-palate may cause NSCPO.

Phenotypic dento-osseous characterization of a Brazilian family with Familial Adenomatous Polyposis

OBJECTIVE

To perform a phenotypic characterization of the dento-osseous anomalies in a Brazilian family with Familial Adenomatous Polyposis (FAP) and to investigate the adenomatous polyposis coli (APC) causative variant.

DESIGN

The study included a family of 14 individuals (Group A: affected; Group B: non-affected). The frequency of radiographic findings in both groups was evaluated according to the Dental Panoramic Radiograph Score (DPRS) diagnostic method. The accuracy and reproducibility of DPRS were tested. The DNA was isolated from the index patient's saliva and submitted to whole-exome and Sanger sequencing approach.

RESULTS

DPRS ≥ 7 was observed in 80 % of Group A but in none of Group B. The most common findings in Group A were dense bone islands (60 %), hazy sclerosis (40 %), osteomas (40 %), and supernumerary tooth (20 %). DPRS has proved to be a reliable method while DPRS ≥ 5 and DPRS ≥ 7 were taken as positive for FAP, and reproducible diagnosis test considering that the evaluators correctly identified the affected patients (Kappa agreement>0.8, p = 0.002). A nonsense heterozygous mutation in the APC gene (c.1370C > G; p.Ser457*) of the index case was detected.

CONCLUSION

FAP patients have a higher frequency of dento-osseous anomalies (p = 0.005). Bone abnormalities were more prevalent than dental anomalies (p = 0.001). Thus, FAP patients should be referred for dental examination and genetic counseling to perform early diagnosis of dento-osseous anomalies and evaluate the implications of the molecular findings in each particular family.