Validation of CFTR intronic variants identified during cystic fibrosis population screening by a minigene splicing assay
-
Gianpietro Giorgi
and
Leonardo Salviati
Abstract
Background: Cystic fibrosis, caused by mutations of the CFTR gene, is the most common autosomal recessive condition in the European population and there are specific screening programs aimed at investigating healthy carriers. They are usually articulated in two steps: initially individuals are screened with a panel of the 20–50 most common CFTR mutations; the second step is offered to partners of carriers who were found negative at the first test and consists in the analysis of the entire CFTR gene. This strategy provides high sensitivity, however, it often identifies novel variants (especially in introns) of unknown significance. Establishing the pathogenicity of these variants of the CFTR gene is not a simple task.
Methods: We have examined five CFTR intronic variants of unclear significance (c.274-6T>C, c.744-6T>G, c.1117-64G>A, c.2620-26A>G, and c.3468+51C>A) using a functional splicing assay based on hybrid minigenes.
Results: Four out of five variants (including c.2620-26A>G which was previously reported as a possible splice-site mutation) did not alter the correct splicing of the minigene and are likely to be neutral polymorphisms, whereas c.744-6T>G caused complete skipping of CFTR exon 7 and should be therefore regarded as a pathogenic CFTR mutation.
Conclusions: Hybrid minigenes assay are a simple and rapid tool to evaluate the effects of intronic variants without the need of analyzing patient’s mRNA, and are particularly suited to analyze variants identified during population screenings.
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©2015 by De Gruyter
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Articles in the same Issue
- Frontmatter
- Editorials
- Laboratory medicine does matter in science (and medicine)… yet many seem to ignore it
- The standardization of the urine albumin assays: no longer deferrable
- Reviews
- The role of telomeres and vitamin D in cellular aging and age-related diseases
- Atypical hemolytic uremic syndrome: from diagnosis to treatment
- Clinical relevance and contemporary methods for counting blood cells in body fluids suspected of inflammatory disease
- EFLM Opinion Paper
- How to assess the quality of your analytical method?
- Genetics and Molecular Diagnostics
- Validation of CFTR intronic variants identified during cystic fibrosis population screening by a minigene splicing assay
- General Clinical Chemistry and Laboratory Medicine
- Uncertainty in measurement for 43 biochemistry, immunoassay, and hemostasis routine analytes evaluated by a method using only external quality assessment data
- A study examining the bias of albumin and albumin/creatinine ratio measurements in urine
- National survey on appropriateness of clinical biochemistry reporting in China
- Potentiometric measurement of urinary iodine concentration in patients with thyroid diseases with and without previous exposure to non-radioactive iodine
- Determination of 21-hydroxylase autoantibodies: inter-laboratory concordance in the Euradrenal International Serum Exchange Program
- Value of a commercial kit for detecting anti-C1q autoantibodies and correlation with immunological and clinical activity of lupus nephritis
- Comparison of the bead-based simultaneous analysis of specific platelet antibodies assay (SASPA) and Pak Lx Luminex technology with the monoclonal antibody immobilization of platelet antigens assay (MAIPA) to detect platelet alloantibodies
- Measurement of the inflammatory response in the early postoperative period after hip and knee arthroplasty
- Whole blood thromboelastometry profiles in women with preeclampsia
- Increased plasma soluble urokinase plasminogen activator receptor levels in systemic sclerosis: possible association with microvascular abnormalities and extent of fibrosis
- Reference Values and Biological Variations
- Reference ranges of serum bile acids in children and adolescents
- Infectious Diseases
- Elevated circulating ghrelin, but not peptide YY(3-36) levels, in term neonates with infection
- Cardiovascular Diseases
- Head-to-head comparison of 10 natriuretic peptide assays
- Prognostic role of BNP in children undergoing surgery for congenital heart disease: analysis of prediction models incorporating standard risk factors
- Elevations of inflammatory markers PTX3 and sST2 after resuscitation from cardiac arrest are associated with multiple organ dysfunction syndrome and early death
- Identification of molecular species of oxidized triglyceride in plasma and its distribution in lipoproteins
- A new formula for estimation of low-density lipoprotein cholesterol in an ethnic Chinese population
- Letter to the Editors
- Laboratory medicine: let’s say it is the mirror of science (and medicine)
- The economic burden of hemolysis
- Acute effects of conventional and extended hemodialysis and hemodiafiltration on high-sensitivity cardiac troponins
- Cuvette carryover with the gentamicin assay on the Beckman AU480 analyser
- Comparison study of two commercially available methods for the determination of golimumab and anti-golimumab antibody levels in patients with rheumatic diseases
- Automated alkaline-pH electrophoresis followed by densitometry does not correlate with cation-exchange (CE)-HPLC in quantification of HbA2 and variant hemoglobins
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- Harmonization of results has not been fully achieved for serum immunoglobulin measurements
- The risk of macrovascular complications in subjects genotyped for common IL-6 gene and TNF-α gene variants
- Comparison of nucleated red blood cell count with four commercial hematological analyzers
- Reply to: The risk of macrovascular complications in subjects genotyped for common IL-6 gene and TNF-α gene variants
- Congress Abstracts
- Congress of Clinical Chemistry and Laboratory Medicine
- 47th National Congress of the Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC – Laboratory Medicine)
- 15th EFLM Continuous Postgraduate Course in Clinical Chemistry and Laboratory Medicine
