Non lethal Raine syndrome and differential diagnosis

• Published in: European journal of medical genetics Vol. 59; no. 11; pp. 577 - 583
• Main Authors: Elalaoui, Siham Chafai, Al-Sheqaih, Nada, Ratbi, Ilham, Urquhart, Jill E, O'Sullivan, James, Bhaskar, Sanjeev, Williams, Simon S, Elalloussi, Mustapha, Lyahyai, Jaber, Sbihi, Leila, Cherkaoui Jaouad, Imane, Sbihi, Abdelhafid, Newman, William G, Sefiani, Abdelaziz
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Masson SAS 01-11-2016
• Subjects: Abnormalities, Multiple - diagnosis; Abnormalities, Multiple - genetics; Abnormalities, Multiple - mortality; Abnormalities, Multiple - physiopathology; Adolescent; Amelogenesis Imperfecta - diagnosis; Amelogenesis Imperfecta - genetics; Amelogenesis Imperfecta - mortality; Amelogenesis Imperfecta - physiopathology; Bone Diseases, Developmental - genetics; Bone Diseases, Developmental - mortality; Bone Diseases, Developmental - physiopathology; Casein Kinase I - genetics; Cleft Palate - diagnosis; Cleft Palate - genetics; Cleft Palate - mortality; Cleft Palate - physiopathology; Dementia - diagnosis; Dementia - genetics; Dementia - mortality; Dementia - physiopathology; Diagnosis, Differential; Epilepsy - diagnosis; Epilepsy - genetics; Epilepsy - mortality; Epilepsy - physiopathology; Exophthalmos - diagnosis; Exophthalmos - genetics; Exophthalmos - mortality; Exophthalmos - physiopathology; Extracellular Matrix Proteins - genetics; FAM20C gene; Female; Humans; Kohlschutter-Tonz syndrome; Learning Disorders - genetics; Learning Disorders - physiopathology; Male; Medical Education; Microcephaly - diagnosis; Microcephaly - genetics; Microcephaly - mortality; Microcephaly - physiopathology; Osteosclerosis - diagnosis; Osteosclerosis - genetics; Osteosclerosis - mortality; Osteosclerosis - physiopathology; Phenotype; Raine syndrome; Seizures - genetics; Seizures - physiopathology; Raine syndrome; FAM20C gene; Kohlschutter-Tonz syndrome
• ISSN: 1769-7212; 1878-0849
• DOI: 10.1016/j.ejmg.2016.09.018

Abstract Raine syndrome is a rare autosomal recessive bone dysplasia characterized by characteristic facial features with exophthalmos and generalized osteosclerosis. Amelogenesis imperfecta, hearing loss, seizures, and intracerebral calcification are apparent in some affected individuals. Originally, Raine syndrome was originally reported as a lethal syndrome. However, recently a milder phenotype, compatible with life, has been described. Biallelic variants in FAM20C, encoding aGolgi casein kinase involved in biomineralisation, have been identified in affected individuals. We report here a consanguineous Moroccan family with two affected siblingsa girl aged 18 and a boy of 15years. Clinical features, including learning disability, seizures and amelogenesis imperfecta, initially suggested a diagnosis of Kohlschutter-Tonz syndrome. However,a novel homozygous FAM20C variantc.676T > A, p.(Trp226Arg) was identified in the affected siblings. Our report reinforces that Raine syndrome is compatible with life, and that mild hypophosphatemia and amelogenesis imperfecta are key features of the attenuated form.