Neuropediatrics 2023; 54(01): 031-036
DOI: 10.1055/a-1947-8411
Original Article

Expanding the Phenotypic Spectrum of Alazami Syndrome: Two Unrelated Spanish Families

1   Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
2   Mitochondrial and Neuromuscular Disorders Group, Hospital 12 de Octubre Health Research Institute (imas12), Madrid, Spain
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
,
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Ana Arteche-López
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
María de los Ángeles Gómez-Cano
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
5   Department of Pediatrics, Endocrinology Unit, 12 de Octubre University Hospital, Madrid, Spain
,
Juan Francisco Quesada-Espinosa
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Carmen Palma Milla
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
José Miguel Lezana Rosales
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Sonia Mayo de Andrés
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
María Teresa Sánchez-Calvín
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
María José Gómez-Rodríguez
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Olalla Sierra Tomillo
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Alexandra Juarez Rufian
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Patricia Ramos Gomez
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
,
Clara Herrero-Forte
6   Clinical Genetics, Clinical Analysis Service, Molecular Diagnostics Unit, Institute of Laboratory Medicine (UDM-IML), Clinico San Carlos University Hospital, Madrid, Spain
7   San Carlos Clinical Research Institute (IdISSC), Madrid, Spain
,
Maria Fenollar-Cortés
6   Clinical Genetics, Clinical Analysis Service, Molecular Diagnostics Unit, Institute of Laboratory Medicine (UDM-IML), Clinico San Carlos University Hospital, Madrid, Spain
7   San Carlos Clinical Research Institute (IdISSC), Madrid, Spain
,
Carmen Cotarelo-Pérez
6   Clinical Genetics, Clinical Analysis Service, Molecular Diagnostics Unit, Institute of Laboratory Medicine (UDM-IML), Clinico San Carlos University Hospital, Madrid, Spain
7   San Carlos Clinical Research Institute (IdISSC), Madrid, Spain
,
Adrián García Ron
8   Neuropaediatrics Unit, Child and Adolescent Institute, Clinico San Carlos University Hospital, Madrid, Spain
,
Olga Pérez Rodríguez
9   Department of Pediatrics, Clinico San Carlos University Hospital, Madrid, Spain
,
Raluca Oancea-Ionescu
6   Clinical Genetics, Clinical Analysis Service, Molecular Diagnostics Unit, Institute of Laboratory Medicine (UDM-IML), Clinico San Carlos University Hospital, Madrid, Spain
7   San Carlos Clinical Research Institute (IdISSC), Madrid, Spain
,
Marta Moreno-García
3   UDISGEN (Unidad de Dismorfología y Genética), 12 de Octubre University Hospital, Madrid, Spain
4   Department of Genetics, 12 de Octubre University Hospital, Madrid, Spain
› Author Affiliations

Abstract

Alazami syndrome is a rare disorder with an autosomal recessive inheritance caused by pathogenic biallelic variants in the LARP7 gene. Clinically, it is mainly characterized by short stature, intellectual disability, and dysmorphic facial features. However, the phenotype is not yet well-defined because less than 50 cases have been described to date. Here, we report three new patients from two unrelated Spanish families who, in addition to the defined features of Alazami syndrome, also exhibit unique features that broaden the phenotypic spectrum of the syndrome. Moreover, we describe the novel frameshift variant c.690_699delins27 in the LARP7 gene, in which loss of function is a known mechanism of Alazami syndrome.

Note

This work has been carried out at the Genetics Service of the Hospital Universitario 12 de Octubre in Madrid.




Publication History

Received: 30 June 2022

Accepted: 30 August 2022

Accepted Manuscript online:
20 September 2022

Article published online:
23 December 2022

© 2022. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
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