Rapid and reliable detection of exon rearrangements in various movement disorders genes by multiplex ligation-dependent probe amplification.
Because of the occurrence of different types of mutations, comprehensive genetic testing for Parkinson's disease (PD), dopa-responsive dystonia (DRD), and myoclonus-dystonia (M-D) should include screening for small sequence changes and for large exonic rearrangements in disease-associated genes. In diagnostic and research settings, the latter is frequently omitted or performed by laborious and expensive quantitative real-time PCR (qPCR). Our study aimed to evaluate the utility of a novel method, multiplex ligation-dependent probe amplification (MLPA), in molecular diagnostics of movement disorders. We have analyzed, by MLPA, genomic DNA from 21 patients affected with PD, DRD, or M-D, in which the presence of exon rearrangement(s) (n = 20) or of a specific point mutation (detectable by MLPA, n = 1) had been established previously by qPCR or sequencing. In parallel, we have studied, in a blinded fashion, DNA from 49 patients with an unknown mutational status. Exon rearrangements were evident in 20 samples with previously established mutations; in the 21st sample the known specific point mutation was detected. We conclude that MLPA represents a reliable method for large-scale and cost-effective gene dosage screening of various movement disorders genes. This finding reaches far beyond a simple technical advancement and has two major implications: (1) By improving the availability of comprehensive genetic testing, it supports clinicians in the establishment of a genetically defined diagnosis; (2) By enabling gene dosage testing of several genes simultaneously, it significantly facilitates the mutational analysis of large patient and control populations and thereby constitutes the prerequisite for meaningful phenotype-genotype correlations.
Department of Neurology, University of Lübeck, Lübeck, Germany.
Ana
A
Djarmati
Miodrag
M
Guzvić
Anne
A
Grünewald
Anthony E
AE
Lang
Peter P
PP
Pramstaller
David K
DK
Simon
Angela M
AM
Kaindl
Peter
P
Vieregge
Anders O H
AO
Nygren
Christian
C
Beetz
Katja
K
Hedrich
Christine
C
Klein
D005091:Exons; D015321:Gene Rearrangement / Q000235:genetics*; D006801:Humans; D009069:Movement Disorders / Q000145:classification / Q000235:genetics*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results