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  • Test code: 04151
  • Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit
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Invitae RASopathies Comprehensive Panel

Test description

The Invitae RASopathies Comprehensive Panel analyzes 18 genes that are members of the mitogen-activated protein kinase (Ras/MAPK) pathway, which is associated with a class of pediatric disorders termed “RASopathies” (also known as Noonan Spectrum Disorders). RASopathies are a class of pediatric disorders whose spectrum of symptoms include distinctive facial features, heart defects, developmental delay, and an increased risk of malignancies.

Proper management by specialists across a variety of disciplines is critical because it is essential that the different disorders be correctly identified and appropriately managed. The Invitae RASopathies Comprehensive panel provides a comprehensive approach to testing individuals who have features that fall within the RASopathies spectrum.

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Primary panel (18 genes)

A2ML1 BRAF CBL HRAS KRAS MAP2K1 MAP2K2 NF1 NRAS PTPN11 RAF1 RASA1 RIT1 RRAS SHOC2 SOS1 SOS2 SPRED1

  • capillary malformation-arteriovenous malformation syndrome (CM-AVM)
  • cardio-facio-cutaneous syndrome (CFC)
  • Costello syndrome
  • Legius syndrome
  • neurofibromatosis type 1 (NF1)
  • Noonan syndrome
  • Noonan syndrome with multiple lentigines (NSML) – formerly known as LEOPARD syndrome

RASopathies are a class of pediatric developmental disorders that share a common spectrum of symptoms, including congenital heart defects, short stature, distinctive craniofacial features, cutaneous abnormalities affecting the skin and hair, varying degrees of developmental delay, and development of tumors, both benign and cancerous. Additional information about each disorder is available by following the links below to their respective condition’s page.

DisorderMain clinical features
Noonan syndrome Characteristic facial features, short stature, congenital heart defects (pulmonary valve stenosis), chest deformities, coagulation and lymphatic deficiencies
Noonan syndrome with multiple lentigines (formerly known as LEOPARD syndrome)Lentigines and café-au-lait macules, hearing loss, congenital heart defects (pulmonary valve stenosis), short stature, increased risk of malignancies
Cardio-facio-cutaneous syndrome Failure to thrive and feeding difficulties, congenital heart defects, characteristic facial features, curly sparse hair and skin rashes, neurologic complications (e.g., hypotonia, motor delay), developmental delay
Costello syndrome Coarse facial features, congenital heart defects, failure to thrive and feeding difficulties, developmental delay and intellectual disability, deep palmar and plantar creases, increased risk of malignancies
Legius syndrome Café-au-lait macules, axillary and inguinal freckling, macrocephaly, lipomas
Neurofibromatosis type 1 Café-au-lait macules, axillary and inguinal freckling, neurofibromas, short stature, macrocephaly
Capillary malformation-arteriovenous malformation syndrome Capillary malformations

The clinical sensitivity of this test is dependent on the patient’s underlying genetic condition. For each condition, the chart below shows the percentage of clinical cases in which a pathogenic variant is expected to be identified through analysis of the genes on this panel.

GeneNoonanNSMLCFCCostelloLegiusNF1CM-AVM
A2ML1 unknown
BRAF <2% rare 75%
CBL <1%
HRAS 80%-90%
KRAS <5% <2%
MAP2K1 <2% 10%-15%
MAP2K2 rare 10%-15%
NF1 ~95%
NRAS rare
PTPN11 50% 90%
RAF1 5%-10% 5%
RASA1 ~70%
RIT1 <2%
RRAS unknown
SHOC2 <1% unknown
SOS1 10%-15% unknown
SOS2 rare
SPRED1 >99%

All RASopathy conditions have an autosomal dominant inheritance pattern.

The RASopathies are highly penetrant conditions whose clinical expression is widely variable, even among family members.

The RASopathies represent one of the largest groups of genetic syndromes, with incidences ranging from a few hundred cases worldwide to approximately 1 in 1,000 individuals.

Estimated prevalence for each syndrome is:

  • Noonan syndrome: 1 in 1000 to 1 in 2500
  • NF1: 1 in 3000
  • CFC: ~1 in 810,000 to 1 in 150,000
  • CM-AVM: ~1 in 100,000
  • Noonan syndrome with multiple lentigines (NSML), Costello syndrome, and Legius syndrome are reportedly rare and their prevalence is currently unknown.

This test may be considered for individuals with:

  • a clinical diagnosis or suspicion of any of the RASopathy disorders
  • a family history of a RASopathy disorder
  • features that are consistent with a RASopathy disorder and negative results from previous molecular testing of select genes

Clinical findings suggestive of RASopathies include short stature, congenital heart defects, developmental delay, broad or webbed neck, unusual chest shape with superior pectus carinatum and inferior pectus excavatum, cryptorchidism, characteristic facies, varied coagulation defects, lymphatic dysplasias, and ocular abnormalities.

  1. Rauen, KA. The RASopathies. Annu Rev Genomics Hum Genet. 2013; 14:355-69. doi: 10.1146/annurev-genom-091212-153523. PMID: 23875798
  2. Tidyman, WE, Rauen, KA. The RASopathies: developmental syndromes of Ras/MAPK pathway dysregulation. Curr. Opin. Genet. Dev. 2009; 19(3):230-6. doi: 10.1016/j.gde.2009.04.001. PMID: 19467855
  3. Smpokou, P, et al. Malignancy in Noonan syndrome and related disorders. Clin. Genet. 2015; :None. doi: 10.1111/cge.12568. PMID: 25683281
  4. Kratz, CP, et al. Cancer spectrum and frequency among children with Noonan, Costello, and cardio-facio-cutaneous syndromes. Br. J. Cancer. 2015; 112(8):1392-7. doi: 10.1038/bjc.2015.75. PMID: 25742478
  5. Yamamoto, GL, et al. Rare variants in SOS2 and LZTR1 are associated with Noonan syndrome. J. Med. Genet. 2015; :None. PMID: 25795793
  6. Cordeddu, V, et al. Activating Mutations Affecting the Dbl Homology Domain of SOS2 Cause Noonan Syndrome. Hum. Mutat. 2015; :None. PMID: 26173643
  7. Aoki, Y, et al. Recent advances in RASopathies. J. Hum. Genet. 2016; 61(1):33-9. PMID: 26446362
  8. Flex, E, et al. Activating mutations in RRAS underlie a phenotype within the RASopathy spectrum and contribute to leukaemogenesis. Hum. Mol. Genet. 2014; 23(16):4315-27. PMID: 24705357
  9. Digilio, MC, et al. RASopathies: Clinical Diagnosis in the First Year of Life. Mol Syndromol. 2011; 1(6):282-289. doi: 10.1159/000331266. PMID: 22190897
  10. Niemeyer, CM. RAS diseases in children. Haematologica. 2014; 99(11):1653-62. doi: 10.3324/haematol.2014.114595. PMID: 25420281
  11. Cizmarova, M, et al. Rasopathies - dysmorphic syndromes with short stature and risk of malignancy. Endocr Regul. 2013; 47(4):217-22. doi: 10.4149/endo_2013_04_217. PMID: 24156711
  12. Rauen, KA, et al. Recent developments in neurofibromatoses and RASopathies: management, diagnosis and current and future therapeutic avenues. Am. J. Med. Genet. A. 2015; 167A(1):1-10. doi: 10.1002/ajmg.a.36793. PMID: 25393061
  13. Allanson, JE, Roberts, AE. Noonan Syndrome. 2001 Nov 15. In: Pagon, RA, et al, editors. GeneReviews (Internet). University of Washington, Seattle; Available from: http://www.ncbi.nlm.nih.gov/books/NBK1124/ PMID: 20301303

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence in the transcript listed below. In addition, analysis covers the select non-coding variants specifically defined in the table below. Any variants that fall outside these regions are not analyzed. Any specific limitations in the analysis of these genes are also listed in the table below.

Based on validation study results, this assay achieves >99% analytical sensitivity and specificity for single nucleotide variants, insertions and deletions <15bp in length, and exon-level deletions and duplications. Invitae's methods also detect insertions and deletions larger than 15bp but smaller than a full exon but sensitivity for these may be marginally reduced. Invitae’s deletion/duplication analysis determines copy number at a single exon resolution at virtually all targeted exons. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. Certain types of variants, such as structural rearrangements (e.g. inversions, gene conversion events, translocations, etc.) or variants embedded in sequence with complex architecture (e.g. short tandem repeats or segmental duplications), may not be detected. Additionally, it may not be possible to fully resolve certain details about variants, such as mosaicism, phasing, or mapping ambiguity. Unless explicitly guaranteed, sequence changes in the promoter, non-coding exons, and other non-coding regions are not covered by this assay. Please consult the test definition on our website for details regarding regions or types of variants that are covered or excluded for this test. This report reflects the analysis of an extracted genomic DNA sample. In very rare cases, (circulating hematolymphoid neoplasm, bone marrow transplant, recent blood transfusion) the analyzed DNA may not represent the patient's constitutional genome.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
A2ML1 NM_144670.4
BRAF NM_004333.4
CBL NM_005188.3
HRAS NM_005343.2
KRAS NM_004985.4
MAP2K1 NM_002755.3
MAP2K2 NM_030662.3
NF1 NM_000267.3
NRAS NM_002524.4
PTPN11 NM_002834.3
RAF1 NM_002880.3
RASA1 NM_002890.2
RIT1 NM_006912.5
RRAS NM_006270.4
SHOC2 NM_007373.3
SOS1 NM_005633.3
SOS2 NM_006939.2
SPRED1 NM_152594.2