title: High-resolution melting analysis, a simple and effective method for reliable mutation scanning and frequency studies in the ACADVL gene.
abstract: Expanded newborn screening uses tandem mass spectrometry (MS/MS) to identify patients affected with fatty acid oxidation defects by the presence of pathological acylcarnitine esters. A caveat to MS/MS assessment is that cut-off values for disease-specific acylcarnitines does not always clearly discriminate affected patients from carriers and healthy individuals. Diagnostic evaluation of screening-positive samples is required to confirm a metabolic deficiency. With MS/MS newborn screening becoming established in a growing number of countries, streamlined means for time- and -effective follow-on diagnostic evaluation is essential. Moreover, studies to evaluate the diagnostic accuracy of MS/MS newborn screening are needed for determination and adjustment of precise cut-off values for the disease-specific acylcarnitines. In the current study, we use the fatty acid oxidation disorder very-long-chain acyl-CoA dehydrogenase deficiency (VLCADD), the second most common fatty acid oxidation disorder detected by expanded newborn screening, to demonstrate accurate and fast diagnostic evaluation of the ACADVL gene utilizing DNA extracted from the newborn screening dried blood spot and high resolution melt (HRM) profiling. We also demonstrate that HRM is a very effective means to determine carrier frequency of prevalent ACADVL mutations in the general population. Based on estimates of the expected disease incidence, we discuss the diagnostic accuracy of MS/MS-based newborn screening to identify VLCADD in Denmark.
authors.affiliation: Research Unit for Molecular Medicine, Aarhus University Hospital, Skejby, Brendstrupgaardsvej, Aarhus N, Denmark. rikke.olsen@ki.au.dk
authors.forename: Rikke Katrine Jentoft
authors.initials: RK
authors.lastname: Olsen
authors.forename: Steven F
authors.initials: SF
authors.lastname: Dobrowolski
authors.forename: Margrethe
authors.initials: M
authors.lastname: Kjeldsen
authors.forename: David
authors.initials: D
authors.lastname: Hougaard
authors.forename: Henrik
authors.initials: H
authors.lastname: Simonsen
authors.forename: Niels
authors.initials: N
authors.lastname: Gregersen
authors.forename: Brage Storstein
authors.initials: BS
authors.lastname: Andresen
mesh_terms: D044942:Acyl-CoA Dehydrogenase, Long-Chain / Q000172:deficiency* / Q000235:genetics*; D004252:DNA Mutational Analysis; D017931:DNA Primers / Q000235:genetics; D003718:Denmark; D005091:Exons; D005227:Fatty Acids / Q000737:chemistry; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D009154:Mutation; D015997:Neonatal Screening / Q000295:instrumentation* / Q000379:methods*; D010100:Oxygen / Q000737:chemistry; D016133:Polymerase Chain Reaction; D015203:Reproducibility of Results
chemical_list: D017931:DNA Primers; D005227:Fatty Acids; D044942:Acyl-CoA Dehydrogenase, Long-Chain; C467805:ACADVL protein, human; D010100:Oxygen