Genetic Investigation and Clinical Aspects in a Romanian Treacher Collins Syndrome Family – A Case Report

Introduction: In approximately 96% of probands, the diagnosis of Treacher Collins Syndrome (TCS) is confirmed by molecular genetic tests. These tests can detect heterozygous mutation of TCOF1 gene (coding treacle protein) and variants of POLR1D gene (coding RNA polymerase I subunit D) with autosomal dominant inheritance, or biallelic variants of POLR1C gene (coding RNA polymerase I subunit C) and POLR1D with autosomal recessive inheritance.

Case presentation: We present a neonate proband with family history of clinical features suggestive for TCS. Our patient was investigated for copy number changes (CNCs) of TCOF1 gene using SALSA MLPA P310-B3 TCOF1 probemix to perform Multiplex Ligation-dependent Probe Amplification (MLPA), the results being normal. Dysmorphic features revealed “bird-like” face with trigonocephaly, craniosynostosis, hypoplastic supraorbital rims, underdeveloped zygomas, mandibular hypoplasia and retrognathia (mandibulofacial dysostosis). Other clinical features, like abnormal position and structure of the external ears (microtia, with a bilateral low-set ears, crumpled and malformed pinnae and aural atresia), were also observed.

Conclusion: Taking into account our results, and also data found in literature, we consider that all TCS cases, but in particular patients with specific TCS features and without CNCs, require additional investigations using sequencing techniques.