Test code: MA1501
The Blueprint Genetics Neurofibromatosis Panel is a seven gene panel.
This panel is ideal for patients whose differential diagnosis includes neurofibromatosis 1 and related disorders, such as Legius syndrome (SPRED1), Noonan syndrome with multiple lentigines syndrome (also knowns as LEOPARD syndrome; PTPN11 and RAF1), and familial schwannomatosis (SMARCB1).
Due to one or more regions of segmental duplication, this panel has reduced sensitivity to detect variants in exons 9-11, 13-29 and 32-36 of NF1. Of the disease causing variants listed in HGMD Professional, 41.2% (1,049/2,547) locates within these pseudogene regions.
The genes on this panel are also included in the Comprehensive Skeletal / Malformation Syndrome Panel.
Neurofibromatosis type 1 and 2 are autosomal dominant conditions. The panel is efficient in differential diagnosis of neurofibromatosis and related disorders, such as Legius syndrome (SPRED1), multiple lentigines syndrome (LEOPARD syndrome; PTPN11 and RAF1), and familial schwannomatosis (SMARCB1). This panel is part of the Comprehensive Skeletal / Malformation Syndrome Panel.
Neurofibromatosis type 1 (NF1) is clinically characterized by multiple café-au-lait spots, axillary and inguinal freckling, multiple cutaneous neurofibromas, and iris Lisch nodules. Learning disabilities are present in at least 50% of patients. Less common but potentially more serious manifestations include plexiform neurofibromas, optic nerve and other central nervous system gliomas, malignant peripheral nerve sheath tumors, scoliosis, tibial dysplasia, and vasculopathy. The clinical features are highly variable, even within the same family. NF1 is caused by heterozygous mutations in the NF1 gene, encoding neurofibromin. About half of the affected individuals have a de novo mutation. NF1 is relatively common inherited disorder, the prevalence is 1:3,000. Neurofibromatosis type 2 (NF2) is a tumour-prone disorder characterised by the development of multiple schwannomas and meningiomas. The hallmark of NF2 is the development of bilateral vestibular schwannomas leading to hearing loss, tinnitus or imbalance or a combination of the three symptoms. The other main tumors are schwannomas of the other cranial, spinal and peripheral nerves; meningiomas both intracranial (including optic nerve meningiomas) and intraspinal, and some low-grade central nervous system malignancies (ependymomas). Ophthalmic features, including reduced visual acuity and cataract are also prominent. Cutaneous features in NF2 are much more subtle than in NF1. About 70% of NF2 patients have skin tumours. NF2 is caused by mutations in the NF2 gene, and more than 50% of patients represent new mutations and as many as one-third are mosaic for the underlying disease-causing mutation. The prevalence of NF2 is 1:60,000. Some syndromes share similar clinical features with NF1 and NF2. Legius syndrome is a very rare condition charaterized by multiple café-au-lait macules with or without axillary or inguinal freckling. About 2% of patients fulfilling diagnostic criteria for NF1 are found to have the genetic mutation underlying Legius syndrome (SPRED1). Familial schwannomatosis is characterized by the development of multiple spinal, peripheral, and cranial-nerve schwannomas in the absence of vestibular schwannomas. It is inherited in an autosomal dominant manner and caused by mutations in SMARCB1. LEOPARD syndrome is a multisystem disorder involving the skin, skeletal and cardiovascular systems. The characteristic feature is brown skin spots called lentigines that are similar to freckles.
Results in 3-4 weeks. We do not offer a maternal cell contamination (MCC) test at the moment. We offer prenatal testing only for cases where the maternal cell contamination studies (MCC) are done by a local genetic laboratory. Read more: http://blueprintgenetics.com/faqs/#prenatal
|KIT||Gastrointestinal stromal tumor||AD||73||109|
|NF1*||Watson syndrome, Neurofibromatosis, Neurofibromatosis-Noonan syndrome||AD||592||2681|
|PTPN11||LEOPARD syndrome, Noonan syndrome, Metachondromatosis||AD||124||135|
|RAF1||LEOPARD syndrome, Noonan syndrome, Dilated cardiomyopathy (DCM)||AD||44||43|
|SMARCB1||Schwannomatosis, Rhabdoid tumor predisposition syndrome||AD||22||115|
*Some regions of the gene are duplicated in the genome leading to limited sensitivity within the regions. Thus, low-quality variants are filtered out from the duplicated regions and only high-quality variants confirmed by other methods are reported out. Read more.
Gene, refers to HGNC approved gene symbol; Inheritance to inheritance patterns such as autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL); ClinVar, refers to a number of variants in the gene classified as pathogenic or likely pathogenic in ClinVar (http://www.ncbi.nlm.nih.gov/clinvar/); HGMD, refers to a number of variants with possible disease association in the gene listed in Human Gene Mutation Database (HGMD, http://www.hgmd.cf.ac.uk/ac/). The list of associated (gene specific) phenotypes are generated from CDG (http://research.nhgri.nih.gov/CGD/) or Orphanet (http://www.orpha.net/) databases.
|Gene||Genomic location HG19||HGVS||RefSeq||RS-number|
The strengths of this test include:
- Blueprint Genetics is one of the few laboratories worldwide with CAP and ISO-15189 accreditation for NGS panels and CLIA certification
- Superior sequencing quality
- Careful selection of genes based on current literature, our experience and the most current mutation databases
- Transparent and easy access to quality and performance data at the patient level that are accessible via our Nucleus portal
- Transparent and reproducible analytical validation for each panel (see Test performance section; for complete details, see our Analytic Validation)
- Sequencing and high resolution del/dup analysis available in one test
- Inclusion of non-coding disease causing variants where clinically indicated (please see individual Panel descriptions)
- Interpretation of variants following ACMG variant classification guidelines
- Comprehensive clinical statement co-written by a PhD geneticist and a clinician specialist
This test does not detect the following:
- Complex inversions
- Gene conversions
- Balanced translocations
- Mitochondrial DNA variants
- Variants in regulatory or non-coding regions of the gene unless otherwise indicated (please see Non-coding disease causing variants covered by the panel). This mean for instance intronic variants locating deeper than 15 nucleotides from the exon-intron boundary.
This test may not reliably detect the following:
- Low level mosaicism
- Stretches of mononucleotide repeats
- Indels larger than 50bp
- Single exon deletions or duplications
- Variants within pseudogene regions/duplicated segments
- Disorders caused by long repetitive sequences (e.g. trinucleotide repeat expansions)
The sensitivity of this test may be reduced if DNA is extracted by a laboratory other than Blueprint Genetics.
For additional information, please refer to the Test performance section and see our Analytic Validation.
Blueprint Genetics offers a comprehensive Neurofibromatosis Panel that covers classical genes associated with legius syndrome, neurofibromatosis, neurofibromatosis type 1, neurofibromatosis type 2 and schwannomatosis. The genes are carefully selected based on the existing scientific evidence, our experience and most current mutation databases. Candidate genes are excluded from this first-line diagnostic test. The test does not recognise balanced translocations or complex inversions, and it may not detect low-level mosaicism. The test should not be used for analysis of sequence repeats or for diagnosis of disorders caused by mutations in the mitochondrial DNA.
Analytical validation is a continuous process at Blueprint Genetics. Our mission is to improve the quality of the sequencing process and each modification is followed by our standardized validation process. Average sensitivity and specificity in Blueprint NGS Panels is 99.3% and 99.9% for detecting SNPs. Sensitivity to for indels vary depending on the size of the alteration: 1-10bps (96.0%), 11-20 bps (88.4%) and 21-30 bps (66.7%). The longest detected indel was 46 bps by sequence analysis. Detection limit for Del/Dup (CNV) analysis varies through the genome depending on exon size, sequencing coverage and sequence content. The sensitivity is 71.5% for single exon deletions and duplications and 99% for three exons’ deletions and duplications. We have validated the assays for different starting materials including EDTA-blood, isolated DNA (no FFPE) and saliva that all provide high-quality results. The diagnostic yield varies substantially depending on the used assay, referring healthcare professional, hospital and country. Blueprint Genetics’ Plus Analysis (Seq+Del/Dup) maximizes the chance to find molecular genetic diagnosis for your patient although Sequence Analysis or Del/Dup Analysis may be cost-effective first line test if your patient’s phenotype is suggestive for a specific mutation profile.
The sequencing data generated in our laboratory is analyzed with our proprietary data analysis and annotation pipeline, integrating state-of-the art algorithms and industry-standard software solutions. Incorporation of rigorous quality control steps throughout the workflow of the pipeline ensures the consistency, validity and accuracy of results. The highest relevance in the reported variants is achieved through elimination of false positive findings based on variability data for thousands of publicly available human reference sequences and validation against our in-house curated mutation database as well as the most current and relevant human mutation databases. Reference databases currently used are the 1000 Genomes Project (http://www.1000genomes.org), the NHLBI GO Exome Sequencing Project (ESP; http://evs.gs.washington.edu/EVS), the Exome Aggregation Consortium (ExAC; http://exac.broadinstitute.org), ClinVar database of genotype-phenotype associations (http://www.ncbi.nlm.nih.gov/clinvar) and the Human Gene Mutation Database (http://www.hgmd.cf.ac.uk). The consequence of variants in coding and splice regions are estimated using the following in silico variant prediction tools: SIFT (http://sift.jcvi.org), Polyphen (http://genetics.bwh.harvard.edu/pph2/), and Mutation Taster (http://www.mutationtaster.org).
Through our online ordering and statement reporting system, Nucleus, the customer can access specific details of the analysis of the patient. This includes coverage and quality specifications and other relevant information on the analysis. This represents our mission to build fully transparent diagnostics where the customer gains easy access to crucial details of the analysis process.
In addition to our cutting-edge patented sequencing technology and proprietary bioinformatics pipeline, we also provide the customers with the best-informed clinical report on the market. Clinical interpretation requires fundamental clinical and genetic understanding. At Blueprint Genetics our geneticists and clinicians, who together evaluate the results from the sequence analysis pipeline in the context of phenotype information provided in the requisition form, prepare the clinical statement. Our goal is to provide clinically meaningful statements that are understandable for all medical professionals, even without training in genetics.
Variants reported in the statement are always classified using the Blueprint Genetics Variant Classification Scheme modified from the ACMG guidelines (Richards et al. 2015), which has been developed by evaluating existing literature, databases and with thousands of clinical cases analyzed in our laboratory. Variant classification forms the corner stone of clinical interpretation and following patient management decisions. Our statement also includes allele frequencies in reference populations and in silico predictions. We also provide PubMed IDs to the articles or submission numbers to public databases that have been used in the interpretation of the detected variants. In our conclusion, we summarize all the existing information and provide our rationale for the classification of the variant.
A final component of the analysis is the Sanger confirmation of the variants classified as likely pathogenic or pathogenic. This does not only bring confidence to the results obtained by our NGS solution but establishes the mutation specific test for family members. Sanger sequencing is also used occasionally with other variants reported in the statement. In the case of variant of uncertain significance (VUS) we do not recommend risk stratification based on the genetic finding. Furthermore, in the case VUS we do not recommend use of genetic information in patient management or genetic counseling. For some cases Blueprint Genetics offers a special free of charge service to investigate the role of identified VUS.
We constantly follow genetic literature adapting new relevant information and findings to our diagnostics. Relevant novel discoveries can be rapidly translated and adopted into our diagnostics without delay. These processes ensure that our diagnostic panels and clinical statements remain the most up-to-date on the market.
Choose an analysis method
ICD & CPT codes
Commonly used ICD-10 codes when ordering the Neurofibromatosis Panel
Accepted sample types
- EDTA blood, min. 1 ml
- Purified DNA, min. 5μg
- Saliva (Oragene DNA OG-500 kit)
Label the sample tube with your patient’s name, date of birth and the date of sample collection.
Note that we do not accept DNA samples isolated from formalin-fixed paraffin-embedded (FFPE) tissue.