ENAM gene polymorphisms associated with dental anomalies in individuals with cleft lip and palate

Aim: This study aimed to investigate the occurrence of enamelin gene (ENAM) single nucleotide polymorphisms (SNP) and ENAM polymorphism association with dental anomalies (DA) in individuals with unilateral or bilateral cleft lip and palate (CLP). Methods: Saliva samples were collected from 147 individuals aged between 6 and 15 years-old, both genders, and divided into 4 groups: Group 1 (G1) - CLP and DA; Group 2 (G2) - CLP without DA; Group 3 (G3) - without CLP with DA; Group 4 (G4) - without CLP and DA. The genomic DNA was extracted from saliva samples and the following ENAM SNPs markers were genotyped: rs3796703, rs3796704, rs3796705, rs7671281, rs2609428, and rs35951442. Fisher exact and Pearson's Chi-square tests statistically analyzed the results (α=5%). Results: Individuals without CLP with DA (Group 3 - 19.2%) showed statistically higher prevalence of SNP rs2609428 heterozygotes (p=0.006) than individuals with CLP and DA (Group 1 - 0%). Individuals without CLP (10%) exhibited statistically higher prevalence of mutated heterozygotes/homozygous (p=0.028) than in individuals with CLP (1.3%). Conclusion: SNP rs2609428 marker of ENAM gene may be associated with dental anomalies in individuals without cleft lip and palate

Triagem de mutações e polimorfismos de genes candidatos à malformação dentária em pacientes com fissura labiopalatinas / Screening of mutations and polymorphisms of candidate genes to dental malformation in patients with cleft lip and palate

O propósito deste trabalho foi investigar a ocorrência de mutações e polimorfismos em genes candidatos aos defeitos na formação do esmalte dentário em indivíduos com fissura labiopalatina (FLP) transforame incisivo unilateral ou bilateral isolada e associar o genótipo-fenótipo dos indivíduos com FLP e malformação dentária (MD) nos dentes incisivos centrais superiores permanentes. Foram coletadas amostras de saliva de 165 indivíduos de 6 a 15 anos de idade, de ambos os sexos, divididos em 4 grupos de estudo: Grupo 1 - 46 indivíduos com FLP e MD; Grupo 2 - 34 indivíduos com FLP e sem MD; Grupo 3 - 34 indivíduos sem FLP e com MD; Grupo 4 - 51 indivíduos sem FLP e MD. Foi realizada a extração do DNA genômico das amostras de saliva, seguida da Reação em Cadeia da Polimerase, sequenciamento direto dos éxons 2, 3, 4, 5, 6 e 7 do gene AMELX e genotipagem dos SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 e rs35951442 no gene ENAM. Para a análise estatística dos resultados foi utilizado o Teste Exato de Fisher e o Teste do Qui-quadrado de Pearson. Em relação ao sequenciamento direto do gene AMELX, mutações foram encontradas em 30,4% (n=14), 35,3% (n=12), 11,8% (n=4) e 13,7% (n=7) dos indivíduos dos Grupos 1, 2, 3 e 4, respectivamente. Trinta e sete mutações foram detectadas e distribuídas ao longo dos éxons 2 (1 mutação - 2,7%), 6 (30 mutações - 81,08%) e 7 (6 mutações - 16,22%) do gene AMELX. Houve um aumento significativo (p=0,003) na frequência de mutações nos indivíduos com FLP (Grupos 1 e 2 - 65,7%) em relação aos indivíduos sem FLP (Grupos 3 e 4 - 25,5%). Em relação às 30 mutações encontradas no éxon 6, 43,34% (n=13), 23,33% (n=7), 13,33% (n=4) e 20% (n=6) foram encontrados nos Grupos 1, 2, 3 e 4, respectivamente. A mutação silenciosa c.261C>T (rs2106416) foi detectada em 26 indivíduos distribuídos nos quatro grupos estudados, sendo significativamente mais encontrada (p=0,003) nos grupos com FLP (23,75%), em comparação com os...

The purpose of this study was to investigate the occurrence of mutations and polymorphisms (SNPs) in candidate genes to defects in the formation of enamel in individuals with cleft lip and palate (CLP) unilateral or bilateral incisive transforame isolated and associate genotype-phenotype of individuals with CLP and dental malformation (DM) in permanent teeth maxillary central incisors. For analysis of the proposed genes, saliva samples from 165 individuals from 6 to 15 years old, of both genders, were collected and divided into 4 groups: Group 1 - 46 individuals with CLP and DM; Group 2 - 34 individuals with CLP and without DM; Group 3 - 34 subjects without CLP and DM; Group 4 - 51 subjects without CLP and DM. Extraction of genomic DNA from saliva samples was performed, followed by Polymerase Chain Reaction, direct sequencing of 2, 3, 4, 5, 6 and 7 exons of AMELX gene and genotyping of SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 and rs35951442 in the ENAM gene. For statistical analysis we used the Fisher's exact test and Pearson's chi-square test. Regarding direct sequencing of AMELX gene, mutations were found in 30.4% (n=14), 35.3% (n=12), 11.8% (n=4) and 13.7% (n=7) of individuals in Groups 1, 2, 3 and 4, respectively. Thirty-seven mutations were detected and distributed over the exons 2 (1 mutation - 2.7%), 6 (30 mutations - 81.08%) and 7 (6 mutations - 16.22%) of AMELX gene. There was a significant increase (p=0.003) in the frequency of mutations in individuals with CLP (Groups 1 and 2 - 65.7%) compared to subjects without CLP (Groups 3 and 4 - 25.5%). Regarding the 30 mutations found in exon 6, 43.34% (n=13), 23.33% (n=7), 13.33% (n=4) and 20% (n=6) were found in Groups 1, 2, 3 and 4, respectively. The c.261C>T silent mutation (rs2106416) was detected in 26 individuals distributed in all groups studied, and was significantly more found (p=0.003) in the groups with CLP (23.75%) compared to the groups without CLP (8.23%). In groups without...

Triagem de mutações e polimorfismos de genes candidatos à malformação dentária em pacientes com fissura labiopalatinas / Screening of mutations and polymorphisms of candidate genes to dental malformation in patients with cleft lip and palate

O propósito deste trabalho foi investigar a ocorrência de mutações e polimorfismos em genes candidatos aos defeitos na formação do esmalte dentário em indivíduos com fissura labiopalatina (FLP) transforame incisivo unilateral ou bilateral isolada e associar o genótipo-fenótipo dos indivíduos com FLP e malformação dentária (MD) nos dentes incisivos centrais superiores permanentes. Foram coletadas amostras de saliva de 165 indivíduos de 6 a 15 anos de idade, de ambos os sexos, divididos em 4 grupos de estudo: Grupo 1 - 46 indivíduos com FLP e MD; Grupo 2 - 34 indivíduos com FLP e sem MD; Grupo 3 - 34 indivíduos sem FLP e com MD; Grupo 4 - 51 indivíduos sem FLP e MD. Foi realizada a extração do DNA genômico das amostras de saliva, seguida da Reação em Cadeia da Polimerase, sequenciamento direto dos éxons 2, 3, 4, 5, 6 e 7 do gene AMELX e genotipagem dos SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 e rs35951442 no gene ENAM. Para a análise estatística dos resultados foi utilizado o Teste Exato de Fisher e o Teste do Qui-quadrado de Pearson. Em relação ao sequenciamento direto do gene AMELX, mutações foram encontradas em 30,4% (n=14), 35,3% (n=12), 11,8% (n=4) e 13,7% (n=7) dos indivíduos dos Grupos 1, 2, 3 e 4, respectivamente. Trinta e sete mutações foram detectadas e distribuídas ao longo dos éxons 2 (1 mutação - 2,7%), 6 (30 mutações - 81,08%) e 7 (6 mutações - 16,22%) do gene AMELX. Houve um aumento significativo (p=0,003) na frequência de mutações nos indivíduos com FLP (Grupos 1 e 2 - 65,7%) em relação aos indivíduos sem FLP (Grupos 3 e 4 - 25,5%). Em relação às 30 mutações encontradas no éxon 6, 43,34% (n=13), 23,33% (n=7), 13,33% (n=4) e 20% (n=6) foram encontrados nos Grupos 1, 2, 3 e 4, respectivamente. A mutação silenciosa c.261C>T (rs2106416) foi detectada em 26 indivíduos distribuídos nos quatro grupos estudados, sendo significativamente mais encontrada (p=0,003) nos grupos com FLP (23,75%)...

The purpose of this study was to investigate the occurrence of mutations and polymorphisms (SNPs) in candidate genes to defects in the formation of enamel in individuals with cleft lip and palate (CLP) unilateral or bilateral incisive transforame isolated and associate genotype-phenotype of individuals with CLP and dental malformation (DM) in permanent teeth maxillary central incisors. For analysis of the proposed genes, saliva samples from 165 individuals from 6 to 15 years old, of both genders, were collected and divided into 4 groups: Group 1 - 46 individuals with CLP and DM; Group 2 - 34 individuals with CLP and without DM; Group 3 - 34 subjects without CLP and DM; Group 4 - 51 subjects without CLP and DM. Extraction of genomic DNA from saliva samples was performed, followed by Polymerase Chain Reaction, direct sequencing of 2, 3, 4, 5, 6 and 7 exons of AMELX gene and genotyping of SNPs rs3796703, rs3796704, rs3796705, rs7671281, rs2609428 and rs35951442 in the ENAM gene. For statistical analysis we used the Fisher's exact test and Pearson's chi-square test. Regarding direct sequencing of AMELX gene, mutations were found in 30.4% (n=14), 35.3% (n=12), 11.8% (n=4) and 13.7% (n=7) of individuals in Groups 1, 2, 3 and 4, respectively. Thirty-seven mutations were detected and distributed over the exons 2 (1 mutation - 2.7%), 6 (30 mutations - 81.08%) and 7 (6 mutations - 16.22%) of AMELX gene. There was a significant increase (p=0.003) in the frequency of mutations in individuals with CLP (Groups 1 and 2 - 65.7%) compared to subjects without CLP (Groups 3 and 4 - 25.5%). Regarding the 30 mutations found in exon 6, 43.34% (n=13), 23.33% (n=7), 13.33% (n=4) and 20% (n=6) were found in Groups 1, 2, 3 and 4, respectively. The c.261C>T silent mutation (rs2106416) was detected in 26 individuals distributed in all groups studied, and was significantly more found (p=0.003) in the groups with CLP (23.75%) compared to the groups without CLP (8.23%). In groups without...

Evaluation of the dentists' knowledge on medical urgency and emergency.

This study aimed at evaluating how well dentists understand medical emergency/urgency procedures and issues during dental treatment at a hospital specialized in cleft lip and palate. It comprised a hundred dentists from the Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC/USP), Brazil, from different dental specialties. A questionnaire was applied to evaluate their knowledge of medical emergencies/urgencies from June through September 2011. The questionnaire was anonymous, confidential and constructed with closed questions and either yes-no or multiple-choice responses. Results showed that most professionals (87%) were trained in basic life support (BLS), but only 43% considered themselves capable of providing first aid and performing the necessary maneuvers. Most participants (94%) claimed that they knew the difference between medical urgencies and emergencies, and 69% had BLS training in their undergraduate courses, as opposed to 37%, during their specialization. Some participants (23%) mentioned that they had received knowledge of the subject during extracurricular courses and/or graduate courses (12%). Only 9% had not been educated on the subject; however, all participants showed interest in attending a course in BLS. In regard to assessing training that dentists who attended BLS courses received, 49% were satisfied and 42% were dissatisfied. Results of the present study emphasize that dentists from HRAC/USP have little knowledge about BLS procedures to perform them. Dentists must gain adequate education and training to minimize possible technical, ethical and legal problems associated with dental practice. It is necessary to improve both knowledge and practice in order to become well-qualified practitioners.

Amelogenin gene influence on enamel defects of cleft lip and palate patients.

The aim of this study was to investigate the occurrence of mutations in the amelogenin gene (AMELX) in patients with cleft lip and palate (CLP) and enamel defects (ED). A total of 165 patients were divided into four groups: with CLP and ED (n=46), with CLP and without ED (n = 34), without CLP and with ED (n = 34), and without CLP or ED (n = 51). Genomic DNA was extracted from saliva followed by conducting a Polymerase Chain Reaction and direct DNA sequencing of exons 2 through 7 of AMELX. Mutations were found in 30% (n = 14), 35% (n = 12), 11% (n = 4) and 13% (n = 7) of the subjects from groups 1, 2, 3 and 4, respectively. Thirty seven mutations were detected and distributed throughout exons 2 (1 mutation - 2.7%), 6 (30 mutations - 81.08%) and 7 (6 mutations - 16.22%) of AMELX. No mutations were found in exons 3, 4 or 5. Of the 30 mutations found in exon 6, 43.34% (n = 13), 23.33% (n = 7), 13.33% (n = 4) and 20% (n = 6) were found in groups 1, 2, 3 and 4, respectively. c.261 C > T (rs2106416), a silent mutation, was detected in 26 subjects, and found more significantly (p = 0.003) in patients with CLP (groups 1 and 2 - 23.75%), compared with those without CLP (groups 3 and 4 - 8.23%). In the groups without ED, this silent mutation was also found more significantly (p = 0.032) among subjects with CLP (17.65% in group 2), compared with those without CLP (7.8% in group 4). In conclusion, this study suggested that AMELX may be a candidate gene for cleft lip and palate.

Amelogenesis imperfecta and screening of mutation in amelogenin gene.

The aim of this study was to report the clinical findings and the screening of mutations of amelogenin gene of a 7-year-old boy with amelogenesis imperfecta (AI). The genomic DNA was extracted from saliva of patient and his family, followed by PCR and direct DNA sequencing. The c.261C>T mutation was found in samples of mother, father, and brother, but the mutation was not found in the sequence of the patient. This mutation is a silent mutation and a single-nucleotide polymorphism (rs2106416). Thus, it is suggested that the mutation found was not related to the clinical presence of AI. Further research is necessary to examine larger number of patients and genes related to AI.