Genetic Autosomal Dominant Disorders: A Knowledge Review / Trastornos Autosómicos Dominantes: Una Revisión de los Conocimientos

Genetic disorders occur by excess or absence of chromosomal material, and the consequence of these changes is reflected in morphological and physiological changes. Autosomal disorders, which have dominant inheritance, as cleidocranial dysostosis, Craniofacial syndrome Apert, Treacher Collins and Achondroplasia have peculiar and similar characteristics. Because of their implications in the dental field, the aim of this review is to report on dysostoses, through exposure of general clinical factors and highlighting the signs in the oral cavity. Articles were selected from Lilacs, PubMed and Bireme databases, included in the year 2007­2014, and the keywords were: cleidocranial dysplasia, craniofacial dysostosis, mandibulofacial dysostosis, dysostosis and oral. Alterations of maxillofacial bones and craniofacial are well documented in the literature, but studies reporting an association between treatment odontologic and dysostoses are scarce. In conclusion, Oral pathological manifestations developed cause difficulty in speech, chewing, breathing, social involvement, and in a general perspective, psychological impairment and physical limitations.

Las enfermedades genéticas se producen debido a un exceso o ausencia de material cromosómico, y la consecuencia de estos cambios se refleja en los cambios morfológicos y fisiológicos. Trastornos autosómicos dominantes que tienen herencia dominante, como la disostosis cleidocraneal, el síndrome craneofacial de Apert, Treacher Collins y acondroplasia tiene características peculiares y similares. Debido a sus implicaciones en el campo de la odontología, el objetivo de esta revisión es hablar, a través de la exposición de los factores clínicos y generales, destacando los signos en la cavidad oral. Se seleccionaron los artículos de las bases de datos Lilacs, PubMed y BIREME, incluyendo los años 2007-2014, y las palabras clave fueron: displasia cleidocraneal, craneofacial mandibulofacial disostosis, disostosis y oral. Los cambios de huesos maxilofaciales y craneofaciales están bien documentados en la literatura, pero los estudios que informaron una asociación entre el tratamiento dental y disostosis son escasos. En conclusion, las manifestaciones orales son causas de dificultades del habla, masticación, respiración y la participación social.

Síndrome de Crouzon: revisão de literatura / Crouzon's syndrome: literature review

Introdução: A síndrome de Crouzon ou Disostose crânio-facial tipo I é uma doença rara, que afeta o desenvolvimento do esqueleto crânio-facial. Apesar de ser incomum, possui 50% de risco de transmissão quando um dos pais é portador. Objetivo: Fazer uma revisão da literatura sobre a Síndrome de Crouzon, enfatizando aspectos atuais. Método: Utilizou-se como metodologia consulta as bases de dados on line Cochrane, LILACS, MEDLINE, OMIM e SciELO, aplicando-se à pesquisa o termo Síndrome de Crouzon para artigos publicados até 2007, além da literatura já consagrada em relação ao assunto. Revisão de Literatura: Esta síndrome é caracterizada por anomalias crânios-faciais causadas por perda precoce de flexibilidade do crânio, presentes desde o nascimento e com tendência a agravar-se com o tempo. Os principais sinais clínicos são craniossinostose, hipertelorismo, exoftalmia, estrabismo externo, "nariz de bico de papagaio", lábio superior curto, hipoplasticidade maxilar e relativo prognatismo mandibular, determinando um aspecto de hipoplasia centrofacial. É uma afecção hereditária com transmissão autossômica dominante com 100% de penetrância e larga escala da expressão fenotípica. Considerações Finais: O aconselhamento genético e o estudo individual de cada caso são fundamentais a fim de se promover o avanço no diagnóstico. É necessária uma abordagem precoce multidisciplinar com programa terapêutico específico objetivando a prevenção dos efeitos de um diagnóstico tardio.

Introduction: The Crouzon syndrome or craniofacial dysostosis type I is a rare disease that affects the craniofacial skeleton development. Although it is uncommon, it has a transmission risk of 50% when one of the parents is a carrier. Objective: Performing a literature review about the Crouzon Syndrome, with emphasis on the current aspects. Method: As a methodology, a search on databases on-line, such as Cochrane, LILACS, MEDLINE, OMIM and SciELO has been made, by applying for the search the key-word Crouzon's Syndrome for articles published until 2007, in addition to the literature already dedicated to the subject. Literature Review: This syndrome is characterized by craniofacial anomalies caused by the early loss of the cranium flexibility, and present since the birth with tendency to aggravation in time. The main clinic signs are craniosynostosis, hypertelorism, exophthalmia, external strabismus, "parrot-beaked nose", short upper lip, hypoplastic maxilla and a relative mandibular prognathism determining a mid-facial hypoplasia aspect. It is a hereditary affection with an autosomal dominant transmission with 100% of penetrance and large phenotypic scale. Final Considerations: The genetic advising and an individual study of each case are essential to promote the improvement of the diagnosis. An early multidisciplinary approach is necessary, with specific therapeutic program aiming at the prevention of late diagnosis effects.

Molecular studies in brazilian patients with muscular dystrophies and craniofacial disorders

This paper presents some of the results of our studies on two distinct groups of disorders: Muscular dystrophies and craniofacial conditions. Among the first, we focused on autosomal recessive (AR) limb-girdle muscular dystrophies (LGMD). To date, there are 8 known loci associated with AR LGMD (LGMD2A, LGMD2B to 2H). We were able to map 2 of these 8 genes through the analysis of large Brazilian families. We also classified 140 patients into one of the seven AR LGMD forms: LGMD2B is the mildest and a clear phenotype-genotype correlation was not observed in most of the cases. Molecular studies on craniofacial disorders have been recently initiated, as exemplified in the text with a discussion on craniosynostosis and cleft lip and/or palate (CL/P). The study of Brazilian patients with craniosynostosis caused by mutations in fibrobrast growth receptor genes (FGFR1-3) allowed us to identify some Apert and Pfeiffer patients with unusual mutations. In addition, about 10 percent of Brazilian patients with coronal synostosis seem to be due to a specific mutation within FGFR3. Finally, our molecular studies on CL/P patients excluded two genes (one, a transforming growth factor and the other involved in folate metabolism) as major candidates for this common malformation. Further studies are being conducted in all the disorder presented in this paper.

Acrofacial dysostosis: a new type?

Entre as síndromes descritas no grupo das Disostoses Acrofaciais, existem dois quadros clínicos que possivelmente representam entidades distintas: as síndromes de Nager e de Miller. Este trabalho relata o caso de um recém-nascido vivo do sexo masculino que apresentava uma síndrome malformativa caracterizada pela seqüência de Robin; orientaçäo antimongolóide das rimas palpebrais; atresia dos meatos acústicos externos; aplasia da ulna e sinostose humero-radial bilateral; 4 ossos metacarpais e 4 dedos com provável ausência do segundo raio digital; ausência da fíbula direita com encurtamento e encurvamento da tíbia, duplicaçäo pielocalicial bilateral. Este caso assim como outros descritos na literatura poderiam representar novos tipos de Disostoses Acrofaciais ou pertencerem ao espectro fenotípico da Síndrome de Nager