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A collection of disease information resources and questions answered by our Genetic and Rare Diseases Information Specialists for Microtia-Anotia. In this paper, the term “microtia” includes anotia as the most severe end .. Several cases reports of mosaicism 46,X,der(Y)t(Y;1)(q12;q21)/ Microtia-anotia is a spectrum of congenital anomalies of the auricle ranging from mild [PubMed]; Okajima H, Takeichi Y, Umeda K, et al.

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This review focuses on malformations of the external ear, and more specifically of the auricles, which are collectively termed microtia. The one occasionally associated with syndromic entities has important implications with regard to its management, treatment and genetic counseling of the patients.

Accordingly, the etiology of microtia-atresia has been related with entities that have an autosomal dominant, autosomal recessive, multifactorial pattern of inheritance as well as alterations in the number of copies of potential genes involved, as suggested by its presence in trisomies 13, 18 and 21, and other unbalanced chromosomal alterations for example, in the partial deletions of 5p, 18p, 18q and 22q Journal of Neonatal-Perinatal Medicine.

It must also be taken into consideration that the alterations in any of the genes involved that lead to the generation of microtia are not limited to the change in the sequence of the nucleotides; one gene without mutations could be subject to epigenetic changes that alter its transcription or the alteration could be found in the molecules that regulate the genetic expression at the post-translational level. In summary, we are compelled to speculate that the Native American shared gene pool may play a role in the occurrence of microtia-anotia making plausible to consider a role of ethnicity in microtia-anotia; this will be further pursued using ancestry informative markers.

However, given the magnitude of some of the differences, other factors may also be involved. Identification of microtia in animal models can be challenging for the following reasons: The median value was 1.

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Sheryl Lewin, MD Medpor surgeon. Incidence of ear diseases in Navajo Indians.

Microtia-Anotia: A Global Review of Prevalence Rates

Programs with active ascertainment presented higher prevalence; which was not surprising as this methodological characteristic is usually related to better validity of data. Am J Med Genet. In addition, the epidemiologic data on the association of OAVS and vascular defects has not been conclusive.

This study contributes to the knowledge on the prevalence of microtia-anotia by providing a critical anotiia of the existing data. According to the judgment of the physician, disorders need to be ruled out at the vertebral, renal and ophthalmological level as well as to carry out hearing tests. The syndromes mentioned are not the only ones in which microtia-atresia has been reported in a high percentage of the cases. Please review our privacy policy.

Among the 8 hospital-based programs there were 3 programs from Central and South America. Familial microtia with meatal atresia in two sibships.

Microtia as an autosomal dominant mutation in a transgenic mouse line: These defects also are thought to be caused by a combination of genes and other factors, h as the things the mother comes in contact with in the environment or what the mother eats or drinks or certain medicines she uses during pregnancy.

Clinical kicrotia and associated anomalies.

Microtia-Anotia: A Global Review of Prevalence Rates

Case report and review of the literature. Intra-uterine growth restriction and increased frequency of preeclampsia and stillbirths are more common in populations living at high altitude than those at low altitude.

Another possibility is a truly high prevalence of anotia in those areas.

Microtia-atresia must be considered as a major malformation with important repercussions in hearing function requiring multidisciplinary medical care in order to limit the disability associated and to provide genetic counseling. SRJ is a prestige metric based on the idea that not all citations are the same.

Microtia: Epidemiology & Genetics

Microtia has been part of the clinical picture in the most common aneuploidies such as trisomy 13 and Birth Defects Orig Artic Ser. Therefore, speech and language development are typically normal, although children aanotia microtia-anotia are at a greater risk of delayed language development and attention deficit disorders Eavey, ; Kelley and Scholes, Atresia is Latin for absence of an opening.


Epidemiology and genetics of microtia-anotia: Migration of the outer ear to their normal placement occurs at 20 weeks. Each case is individual and will have its own requirements for care depending on the type of lesion and if it is uni- or bilateral or if it is believed that it can be isolated or is syndromic.

As the genetic control of embryonic tissue morphogenesis is better understood, we may discover that the existing classification systems are too simplistic to be used in the study of normal and abnormal ear development. Ear Community Wishes To Thank: The role of neural crest cells in the etiology and pathogenesis of Treacher Collins syndrome and the potential for prevention.

Microtia & Atresia

The success of such investigations requires high-quality phenotypic data. Tbx1 In mice, mutations in Tbx1a member of the T-box gene family of transcription factors, result in failure of middle and outer ear development and in hypoplasia of the inner ear sensory organs. Detailed description of the malformation of each component of the ear, and acquisition of corresponding images should be the standard for recording information on microtia and other birth defects, regardless of the classification system chosen.

Adolfo Correa and Dr. If it has also been established that there is a hereditary family history or if there was exposure to possible teratogens, etc. Dominant mutation of the murine Hox Anotia only For the 61 surveillance programs that reported only anotia or anotia discriminated from microtia, among 32, births; 1, cases of anotia were diagnosed, with an overall prevalence of 0.

CNV could influence gene expression by interrupting genes or altering the gene dose. New findings in model systems driving future directions for microtia research. Absent outer ear Severely affected middle ear. Parental education and support are essential, and local, regional and national organizations may be very helpful. Transcription factor SIX5 is mutated in patients with branchio-oto-renal syndrome. J Am Acad Dermatol.