High frequency of ribosomal protein gene deletions in Italian Diamond-Blackfan anemia patients detected by multiplex ligation-dependent probe amplification assay
Paola Quarello,
Emanuela Garelli,
Alfredo Brusco,
Adriana Carando,
Cecilia Mancini,
Patrizia Pappi,
Luciana Vinti,
Johanna Svahn,
Irma Dianzani,
Ugo Ramenghi
Affiliations
Paola Quarello
Pediatric Onco-Hematology, Regina Margherita Children's Hospital, Turin
Emanuela Garelli
Hematology Unit, Department of Pediatrics, University of Turin
Alfredo Brusco
Department of Genetics, Biology and Biochemistry, University of Turin;Medical Genetics Unit, San Giovanni Battista Hospital, Turin
Adriana Carando
Hematology Unit, Department of Pediatrics, University of Turin
Cecilia Mancini
Department of Genetics, Biology and Biochemistry, University of Turin
Patrizia Pappi
Medical Genetics Unit, San Giovanni Battista Hospital, Turin
Luciana Vinti
Department of Hematology-Oncology, Paediatric Hospital Bambino Gesù, Rome
Johanna Svahn
Hematology Unit, G. Gaslini Children's Hospital, Genoa
Irma Dianzani
Department of Health Sciences, University of Eastern Piedmont, Novara;IRCAD Interdisciplinary Research Center of Autoimmune Diseases, Novara, Italy
Ugo Ramenghi
Hematology Unit, Department of Pediatrics, University of Turin;IRCAD Interdisciplinary Research Center of Autoimmune Diseases, Novara, Italy
Diamond-Blackfan anemia is an autosomal dominant disease due to mutations in nine ribosomal protein encoding genes. Because most mutations are loss of function and detected by direct sequencing of coding exons, we reasoned that part of the approximately 50% mutation negative patients may have carried a copy number variant of ribosomal protein genes. As a proof of concept, we designed a multiplex ligation-dependent probe amplification assay targeted to screen the six genes that are most frequently mutated in Diamond-Blackfan anemia patients: RPS17, RPS19, RPS26, RPL5, RPL11, and RPL35A. Using this assay we showed that deletions represent approximately 20% of all mutations. The combination of sequencing and multiplex ligation-dependent probe amplification analysis of these six genes allows the genetic characterization of approximately 65% of patients, showing that Diamond-Blackfan anemia is indisputably a ribosomopathy.
