Pulmonary Arterial Hypertension

Pulmonary Arterial Hypertension (PAH) Panel, Sequencing and Deletion/Duplication 2009345
Method: Massively Parallel Sequencing/Exonic Oligonucleotide-based CGH Microarray

Preferred test to confirm a diagnosis of PAH, especially in those with a family history of PAH

Pulmonary Arterial Hypertension (BMPR2) Sequencing and Deletion/Duplication 2003405
Method: Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification

Acceptable test for individuals with clinical symptoms of PAH

Pulmonary Arterial Hypertension (BMPR2) Sequencing 2003410
Method: Polymerase Chain Reaction/Sequencing

Alternate test for individuals with clinical symptoms of PAH 

EIF2AK4-Associated Disorders (EIF2AK4) Sequencing 2010696
Method: Polymerase Chain Reaction/Sequencing

Preferred test to confirm diagnosis or assess carrier status for an EIF2AK4-associated disorder such as pulmonary capillary hemangiomatosis (PCH) and pulmonary veno-occlusive disease (PVOD)

Familial Mutation, Targeted Sequencing 2001961
Method: Polymerase Chain Reaction/Sequencing
  • Recommended test if there is a known familial sequence variant previously identified in a family member.
  • A copy of the family member’s lab report documenting the known familial variant is required.

Pulmonary arterial hypertension (PAH) is caused by widespread occlusion or destruction of the smallest pulmonary arteries, leading to increased blood flow resistance, right ventricular hypertrophy, and heart failure. Genetic testing is most appropriate when no obvious etiology for pulmonary hypertension is found or if a family history of PAH exists.

Disease Overview

Symptoms

  • Shortness of breath
  • Fatigue
  • Syncope
  • Chest pain
  • Palpitations
  • Edema

Epidemiology 

Incidence – 1-2/million

Inheritance 

  • Autosomal dominant – ACVRL1, BMPR2, CAV1, ENG, KCNA5, KCNK3, and SMAD9 
  • Autosomal recessive – EIF2AK4

Test Description 

See Genes Tested table for genes included in the panel.

Clinical Sensitivity

  • 75-80% for familial cases (Austin, 2017;Garcia-Rivas, 2017)
  • ~25% for simplex cases (Austin, 2017; Garcia-Rivas 2017)

Limitations

  • A negative result does not exclude a heritable form of pulmonary arterial hypertension.
  • Diagnostic errors can occur due to rare sequence variations.
  • Interpretation of this test result may be impacted if the individual has had an allogeneic stem cell transplantation.
  • The following will not be evaluated:
    • Variants outside the coding regions and intron-exon boundaries of the targeted genes
    • Regulatory region variants and deep intronic variants 
    • Breakpoints of large deletions/duplications
    • Deletions/duplications in KCNA5
    • Noncoding transcripts
  • The following may not be detected:
    • Deletions/duplications/insertions of any size by massively parallel sequencing
    • Deletions/duplications less than 1kb in the targeted genes by array
    • Some variants due to technical limitations in the presence of pseudogenes, repetitive, or homologous regions
    • Low-level somatic variants 
    • Single exon deletions/duplications in the following exons:
      • EIF2AK4 (NM_001013703) 2, 5, 29, 34, 35

Analytical Sensitivity

For massively parallel sequencing:

Variant Class Analytical Sensitivity (PPA) Estimatea (%) Analytical Sensitivity (PPA) 95% Credibility Regiona (%)

SNVs

99.2

96.9-99.4

Deletions 1-10 bp

93.8

84.3-98.2

Deletions 11-44 bp

100

87.8-100

Insertions 1-10 bp

94.8

86.8-98.5

Insertions 11-23 bp

100

62.1-100

aGenes included on this test are a subset of a larger methods-based validation from which the PPA values are derived.

bp, base pairs; PPA, positive percent agreement; SNVs, single nucleotide variants

Genes Tested

Gene MIM Number Disorder PAH Attributable to Gene

ACVRL1

601284

HHT type 2

1%

BMPR2

600799

BMPR2-related PAH; PAH1; PVOD type 1

~75% of familial cases; ~25% of simplex cases

CAV1

601047

PAH3

~1%

EIF2AK4

609280

PVOD2

>10%

ENG

131195

HHT type 1

~1%

KCNA5

176267

Familial atrial fibrillation-7

Unknown

KCNK3

603220

PAH4

~1-3%

SMAD9

603295

PAH2

Unknown

HHT, hereditary hemorrhagic telangiectasia; PAH, pulmonary arterial hypertension; PCH, pulmonary capillary hemangiotomatosis; PVOD, pulmonary veno-occlusive disease
References 

Austin E, Loyd J, III JP. Heritable Pulmonary Arterial Hypertension. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews, University of Washington, 1993-2018. Seattle, WA [Last Update: Jun 2015; Accessed: Nov 2018]

Austin ED, Loyd JE. The genetics of pulmonary arterial hypertension. Circ Res. 2014; 115(1): 189-202. PubMed

Garcia-Rivas G, Jerjes-Sánchez C, Rodriguez D, Garcia-Pelaez J, Trevino V. A systematic review of genetic mutations in pulmonary arterial hypertension. BMC Med Genet. 2017; 18(1): 82. PubMed

Ma L, Chung WK. The role of genetics in pulmonary arterial hypertension. J Pathol. 2017; 241(2): 273-280. PubMed

Ma L, Roman-Campos D, Austin ED, Eyries M, Sampson KS, Soubrier F, Germain M, Trégouët D, Borczuk A, Rosenzweig EB, Girerd B, Montani D, Humbert M, Loyd JE, Kass RS, Chung WK. A novel channelopathy in pulmonary arterial hypertension. N Engl J Med. 2013; 369(4): 351-361. PubMed

Prins KW, Thenappan T. World Health Organization Group I Pulmonary Hypertension: Epidemiology and Pathophysiology. Cardiol Clin. 2016; 34(3): 363-74. PubMed

Scientific Leadership Council. Genetic Testing and Counseling for Idiopathic and Familial Pulmonary Arterial Hypertension (PAH). Pulmonary Hypertension Association. [Last Revised: Nov 2008; Accessed: Nov 2018]

Related Information 
Pulmonary Arterial Hypertension - PAH

Last Update: February 2019