DNA sequencing errors in molecular diagnostics of filamin myopathy.

Abstract

BACKGROUND:

Filamin myopathy is a neuromuscular disorder manifesting with predominantly limb-girdle muscle weakness and in many patients with diaphragm paralysis and cardiomyopathy, caused by mutations in the filamin C (FLNC) gene. Molecular diagnosis of filamin myopathy based on direct DNA sequencing of coding exons is compromised by the presence of a high homology pseudogene (pseFLNC) located approximately 53.6 kb downstream of the functional FLNC gene on chromosome 7q.

METHODS:

Molecular cloning, RT-PCR and real-time PCR methods were used to detect sequence differences between the FLNC and pseFLNC that are implicated in known or potential molecular diagnostic errors. Overall, 50 patients with a phenotype resembling filamin myopathy have been screened for mutations in FLNC.

RESULTS:

FLNC sequence inconsistencies caused by the interference from pseFLNC were identified and diagnostic errors involving, in particular, the detection of the most frequent disease-causing FLNC p.W2710X mutation resolved. Mismatches between the FLNC and pseFLNC sequences were tabulated for future use.

CONCLUSIONS:

We devise a strategy that allows one to discern mutations occurring in the functional FLNC from those harbored in pseFLNC, thus preventing possible complications in future research and patient genetic testing.

• Authors: Zagaa Odgerel, Peter F M van der Ven, Dieter O Fürst, Lev G Goldfarb
• Journal: Clinical chemistry and laboratory medicine (Clin Chem Lab Med) Vol. 48 Issue 10 Pg. 1409-14 (Oct 2010) ISSN: 1437-4331 [Electronic] Germany
• PMID: 20578970 (Publication Type: Journal Article, Research Support, N.I.H., Intramural, Research Support, Non-U.S. Gov't)

Chemical References

• Contractile Proteins
• FLNC protein, human
• Filamins
• Microfilament Proteins
• DNA

Topics

• Base Sequence
• Chromosomes, Human, Pair 7 (genetics)
• Cloning, Molecular
• Contractile Proteins (genetics)
• DNA (genetics)
• Exons
• Filamins
• Humans
• Microfilament Proteins (genetics)
• Molecular Diagnostic Techniques
• Muscular Diseases (diagnosis, genetics)
• Mutation
• Reverse Transcriptase Polymerase Chain Reaction
• Sequence Analysis, DNA