genetic study of the association of ear and oral anomalies

ABSTRACT

The study included 43 cases presenting with ear anomalies. All revealed associated oral anomalies. The pattern of association of ear and oral anomalies in each syndrome was studied for accurate phenotypic delineation of these syndromes. The cases represented 11 different genetic syndromes and were classified into seven groups, namely Cornelia de Lange, Smith Lemli Opitz [S.L.O.]. Seckel, Coffin-Siris, Treacher Collins, Rubinstein Taybi and other syndromes with deafness. The low set ear was a common finding in the Cornelia de Lange and the Coffin Siris syndromes. Hearing loss was present in some cases of both syndromes being conductive in Coffin Siris syndrome and variable in Cornelia de Lange syndrome. High arched palate was observed in both syndromes, lips were small "thin" in de Lange and large "thick" in Coffin Siris and philtrum was long in de Lange and short in Coffin Siris syndrome. Macroglossia was only observed in Coffin Siris and Mucopolysaccharidosis syndromes. Posteriorly rotated large ears were observed in both the S.L.O. and the Rubinstein Taybi syndromes. However, ears were protruding in S.L.P. and low set and cupped in Rubinstein Taybi. The palate was high arched in S.L.O., but Rubinstein-Taybi showed in addition narrow and cleft palate. High arched narrow palate was only present among the Rubinstein Taybi syndrome cases. Small ears with or absent lobule were common findings in Seckel syndrome associated with micrognathia. Small ears with malformed helices were constant in all cases of Treacher Collins syndrome and conductive hearing loss was common. This was associated with hypoplastic maxilla and mandible. Sensorineural hearing loss was present in the three cases with Warrdenburg syndrome and was associated with high palate in all. These associations might be explained on the basis of single gene defect causing each syndrome, but additionally we can not ignore the effect of environmental familial interaction during the period of ear and oral embryogenesis