title: A rare subclinical or mild type of Becker muscular dystrophy caused by a single exon 48 deletion of the dystrophin gene.
abstract: In the material of 227 families with Becker muscular dystrophy (BMD), we found nine non-consanguineous families with 17 male individuals carrying a rare mutation-a single exon 48 deletion of the dystrophin gene-who were affected with a very mild or subclinical form of BMD. They were usually detected thanks to accidental findings of elevated serum creatine phosphokinase (sCPK). A thorough clinical analysis of the carriers, both children (12) and adults (5), revealed in some of them muscle hypotonia (10/17) and/or very mild muscle weakness (9/17), as well as decreased tendon reflexes (6/17). Adults, apart from very mild muscle weakness and calf hypertrophy in some, had no significant abnormalities on neurological assessments and had good exercise tolerance. Parents of the children carriers of the exon 48 deletion are usually unaware of their children being affected, and possibly at risk of developing life-threatening cardiomyopathy. The same concerns the adult male carriers. Therefore, the authors postulate undertaking preventive measures such as cascade screening of the relatives of the probands. Newborn screening programmes of Duchenne muscular dystrophy (DMD)/BMD based on sCPK marked increase may be considered.
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland.
authors.forename: Janusz G
authors.initials: JG
authors.lastname: Zimowski
authors.affiliation: Department of Pediatrics and Neurology for Children and Adolescents, Medical University of Silesia, ul. Medyków 16, 40-752, Katowice, Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Pilch
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Pawelec
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland.
authors.forename: Joanna K
authors.initials: JK
authors.lastname: Purzycka
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Kubalska
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Ziora-Jakutowicz
authors.affiliation: Children's Neurology Ward, Dr. E. Hanke Centre of Pediatrics and Oncology of Chorzów, ul. Truchana 7, 41-500, Chorzów, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Dudzińska
authors.affiliation: Department of Genetics, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957, Warszawa, Poland. zaremba@ipin.edu.pl.
authors.forename: Jacek
authors.initials: J
authors.lastname: Zaremba
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D016189:Dystrophin / Q000235:genetics*; D005091:Exons; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics*; D010375:Pedigree; D017384:Sequence Deletion
chemical_list: D016189:Dystrophin
keywords: Asymptomatic mutations; Dystrophin gene; Dystrophinopathy; Exon 48 deletion; Subclinical BMD