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Title: Asymptomatic dystrophinopathy

Abstract

A 4-year-old girl was referred for evaluation for a mild but persistent serum aspartate aminotransferase (AST) elevation detected incidentally during routine blood screening for a skin infection. Serum creatine kinase activity was found to be increased. Immuno-histochemical study for dystrophin in her muscle biopsy showed results consistent with a carrier state for muscular dystrophy. Molecular work-up showed the proposita to be a carrier of a deletion mutation of exon 48 of the dystrophin gene. Four male relatives also had the deletion mutation, yet showed no clinical symptoms of muscular dystrophy (age range 8-58 yrs). Linkage analysis of the dystrophin gene in the family showed a spontaneous change of an STR45 allele, which could be due to either an intragenic double recombination event, or CA repeat length mutation leading to identical size alleles. To our knowledge, this is the first documentation of an asymptomatic dystrophinopathy in multiple males of advanced age. Based on molecular findings, this family would be given a diagnosis of Becker muscular dystrophy. This diagnosis implies the development of clinical symptoms, even though this family is clearly asymptomatic. This report underscores the caution which must be exercised when giving presymptomatic diagnoses based on molecular studies. 28 refs., 4more » figs., 1 tab.« less

Authors:
 [1]; ;  [2]
  1. Univ. of Pittsburgh School of Medicine, PA (United States)|[Univ. of Florence (Italy)
  2. Univ. of Pittsburgh School of Medicine, PA (United States) [and others
Publication Date:
OSTI Identifier:
525998
Resource Type:
Journal Article
Resource Relation:
Journal Name: American Journal of Medical Genetics; Journal Volume: 69; Journal Issue: 3; Other Information: PBD: 31 Mar 1997
Country of Publication:
United States
Language:
English
Subject:
55 BIOLOGY AND MEDICINE, BASIC STUDIES; PATIENTS; HEREDITARY DISEASES; PHENOTYPE; DIAGNOSIS; GENETICS; HUMAN X CHROMOSOME; GENETIC MAPPING; GENES; DNA SEQUENCING; GENE MUTATIONS; GENE RECOMBINATION; MUSCLES; DETECTION; AMINOTRANSFERASES; POLYMERASE CHAIN REACTION

Citation Formats

Morrone, A., Hoffman, E.P., and Hoop, R.C. Asymptomatic dystrophinopathy. United States: N. p., 1997. Web. doi:10.1002/(SICI)1096-8628(19970331)69:3<261::AID-AJMG9>3.0.CO;2-O.
Morrone, A., Hoffman, E.P., & Hoop, R.C. Asymptomatic dystrophinopathy. United States. doi:10.1002/(SICI)1096-8628(19970331)69:3<261::AID-AJMG9>3.0.CO;2-O.
Morrone, A., Hoffman, E.P., and Hoop, R.C. Mon . "Asymptomatic dystrophinopathy". United States. doi:10.1002/(SICI)1096-8628(19970331)69:3<261::AID-AJMG9>3.0.CO;2-O.
@article{osti_525998,
title = {Asymptomatic dystrophinopathy},
author = {Morrone, A. and Hoffman, E.P. and Hoop, R.C.},
abstractNote = {A 4-year-old girl was referred for evaluation for a mild but persistent serum aspartate aminotransferase (AST) elevation detected incidentally during routine blood screening for a skin infection. Serum creatine kinase activity was found to be increased. Immuno-histochemical study for dystrophin in her muscle biopsy showed results consistent with a carrier state for muscular dystrophy. Molecular work-up showed the proposita to be a carrier of a deletion mutation of exon 48 of the dystrophin gene. Four male relatives also had the deletion mutation, yet showed no clinical symptoms of muscular dystrophy (age range 8-58 yrs). Linkage analysis of the dystrophin gene in the family showed a spontaneous change of an STR45 allele, which could be due to either an intragenic double recombination event, or CA repeat length mutation leading to identical size alleles. To our knowledge, this is the first documentation of an asymptomatic dystrophinopathy in multiple males of advanced age. Based on molecular findings, this family would be given a diagnosis of Becker muscular dystrophy. This diagnosis implies the development of clinical symptoms, even though this family is clearly asymptomatic. This report underscores the caution which must be exercised when giving presymptomatic diagnoses based on molecular studies. 28 refs., 4 figs., 1 tab.},
doi = {10.1002/(SICI)1096-8628(19970331)69:3<261::AID-AJMG9>3.0.CO;2-O},
journal = {American Journal of Medical Genetics},
number = 3,
volume = 69,
place = {United States},
year = {Mon Mar 31 00:00:00 EST 1997},
month = {Mon Mar 31 00:00:00 EST 1997}
}
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