Open AccessA Recurrent Variant in <b><i>POLR1B</i></b>, c.3007C>T; p.Arg1003Cys, Associated with Atresia of the External Canal and Microtia in Treacher Collins Syndrome Type 4
Author(s) -
Yumi Enomoto,
Yoshinori Tsurusaki,
Mitsuhiro Tominaga,
Shinji Kobayashi,
Maki Inoue,
Kazutoshi Fujita,
Tatsuro Kumaki,
Hiroaki Murakami,
Kenji Kurosawa
Publication year - 2021
Publication title -
molecular syndromology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.609
H-Index - 36
eISSN - 1661-8777
pISSN - 1661-8769
DOI - 10.1159/000513224
Subject(s) - microtia , hypoplasia , atresia , medicine , genetics , biology , anatomy
Treacher Collins syndrome (TCS) is a heterogenous malformation syndrome characterized by a distinct facial appearance including downslanting palpebral fissures, malar hypoplasia, conductive hearing loss, and mandibular hypoplasia. Recently, a new causative gene, POLR1B , encoding DNA-directed RNA polymerase I subunit RPA2, was identified as a fourth type of TCS (TCS4). We describe another patient with TCS4 caused by a recurrent POLR1B variant, c.3007C>T; p.Arg1003Cys. Including our patient, all 4 patients with p.(Arg1003Cys) had atresia of the external auditory canal and microtia. All of the reported pathogenic variants in POLR1B were clustered at only 2 residues. Our patient highlights the genotype-phenotype correlation in TCS4 associated with POLR1B .