Saethre-Chotzen syndrome, Pro136His TWIST mutation, hearing loss, and external and middle ear structural anomalies: report on a Brazilian family.
OBJECTIVE
To describe the clinical, speech, hearing, and imaging findings in three members of a Brazilian family with Saethre-Chotzen syndrome (SCS) who presented some unusual characteristics within the spectrum of the syndrome.


METHODS
Clinical evaluation was performed by a multidisciplinary team. Direct sequencing of the polymerase chain reaction-amplified coding region of the TWIST1 gene, routine and electrophysiological hearing evaluation, speech evaluation, and imaging studies through computed tomography (CT) scan and magnetic resonance imaging (MRI) were performed.


RESULTS
TWIST1 gene analysis revealed a Pro136His mutation in all patients. Hearing evaluation showed peripherial and mixed hearing loss in two of the patients, one of them with severe unilateral microtia. Computed tomography scan showed structural middle ear anomalies, and MRI showed distortion of the skull contour as well as some of the brain structures.


CONCLUSIONS
We report a previously undescribed TWIST1 gene mutation in patients with SCS. There is evidence that indicates hearing loss (conductive and mixed) can be related both with middle ear (microtia, high jugular bulb, and enlarged vestibules) as well as with brain stem anomalies. Here we discuss the relationship between the gene mutation and the clinical, imaging, speech, and hearing findings.
Lamônica
Dionísia A C
DA
University of São Paulo, College of Dentistry, Speech-Pathology and Audiology Department, Bauru, SP, Brazil.
Maximino
Luciana P
LP
Feniman
Mariza Ribeiro
MR
Silva
Greyce K
GK
Zanchetta
Sthella
S
Abramides
Dagma V M
DV
Passos-Bueno
Maria Rita
MR
Rocha
Kátia
K
Richieri-Costa
Antonio
A
D000168:Acrocephalosyndactylia / Q000235:genetics*; D000293:Adolescent; D001299:Audiometry / Q000379:methods; D001921:Brain / Q000002:abnormalities; D001938:Brazil; D002648:Child; D004431:Ear, External / Q000002:abnormalities*; D004432:Ear, Middle / Q000002:abnormalities*; D005260:Female; D006314:Hearing Loss, Conductive / Q000235:genetics; D046089:Hearing Loss, Mixed Conductive-Sensorineural / Q000235:genetics*; D006639:Histidine / Q000235:genetics*; D006801:Humans; D007807:Language Tests; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*; D011392:Proline / Q000235:genetics*; D013701:Temporal Bone / Q000002:abnormalities; D014057:Tomography, X-Ray Computed / Q000379:methods; D051879:Twist-Related Protein 1 / Q000235:genetics*
D009687:Nuclear Proteins; C103173:TWIST1 protein, human; D051879:Twist-Related Protein 1; D006639:Histidine; D011392:Proline