This gene sequencing panel includes both sequencing and deletion/duplication (CNV) analysis for all coding regions of the included genes (unless otherwise noted). All analysis is performed utilizing next-generation sequencing (NGS) technology. All variants are classified according to American College of Genetics and Genomics (ACMG) guidelines.

Marfan syndrome is a genetic connective tissue disorder that affects various systems in the body. Skeletal phenotypes in indiiduals with Marfan syndrome include tall stature, long limbs, joint hypermobility, and a disproportionately long and narrow face, high-arched palate, scoliosis, and a chest that may protrude or indent, known as pectus excavatum or pectus carinatum. Ocular Abnormalities include myopia, increased risk of retinal detachment, and ectopia lentis, which can cause blurry vision or other visual disturbances. The most serious complications of Marfan syndrome are cardiovascular and include aortic root dilation, dissection, or aortic rupture, mitral valve prolapse, aortic valve regurgitation, and cardiomegaly. Some individuals with Marfan syndrome may experience spontaneous pneumothorax or sleep apnea.

Thoracic aortic aneurysm and dissection (TAAD) encompasses two related but distinct pathological processes. Aortic aneurysm is a dilation or bulge in the arterial wall, which may be asymptomatic or, depending on the size and location, cause symptoms such as chest or back pain, shortness of breath, coughing, hoarseness, and difficulty swallowing. Aortic dissection is a tear or rupture in the inner layer of the aortic wall that allows blood to enter and separate the layers of the vessel. This can lead to the formation of a false lumen within the aorta, compromising blood flow and causing severe pain. Familial TAAD can be caused by an underlying syndromic genetic condition such as Marfan syndrome, Ehlers-Danlos syndrome, or Loeys-Dietz syndrome.

ACTA2, BGN, CBS, COL3A1, COL5A1, COL5A2, FBN1, FBN2, FLNA, LOX, MED12, MFAP5, MYH11, MYLK, NOTCH1, PRKG1, SKI, SLC2A10, SMAD2, SMAD3, SMAD4, TGFB2, TGFB3 TGFBR1, TGFBR2,

Sequencing is performed on genomic DNA using an Agilent targeted sequence capture method to enrich for the exome. Direct sequencing of the amplified captured regions was performed using 2X150bp reads on Illumina next generation sequencing (NGS) systems. A base is considered to have sufficient coverage at 20X and an exon is considered fully covered if all coding bases plus three nucleotides of flanking sequence on either side are covered at 20X or more. A list of these regions, if any, is available upon request. Alignment to the human reference genome (GRCh37) is performed and annotated variants are identified in the targeted region. Variants reviewed have a minimum coverage of 8X and an alternate allele frequency of 20% or higher. Indel and single nucleotide variants (SNVs) may be confirmed by Sanger sequence analysis before reporting at director discretion. This assay cannot detect variants in regions of the exome that are not covered, such as deep intronic, promoter and enhancer regions, areas containing large numbers of tandem repeats, and variants in mitochondrial DNA. Copy number variation (CNV) analysis detects deletions and duplications; in some instances, due to the size of the exons, sequence complexity, or other factors, not all CNVs may be analyzed or may be difficult to detect. When reported, copy number variant size is approximate. Actual breakpoint locations may lie outside of the targeted regions. CNV analysis will not detect tandem repeats, balanced alterations (reciprocal translocations, Robertsonian translocations, inversions, and balanced insertions), methylation abnormalities, triploidy, and genomic imbalances in segmentally duplicated regions. This assay is not designed to detect mosaicism; possible cases of mosaicism may be investigated at the discretion of the laboratory director. Primary data analysis is performed using Illumina bcl2fastq converter v2.19. Secondary analysis is performed using Illumina DRAGEN Bio-IT Platform v.3.10.8. Tertiary data analysis is performed using SnpEff v5.0 and Revvity Omics’ internal ODIN v.1.01 software. CNV and absence of heterozygosity are assessed using BioDiscovery’s NxClinical v6.1 software.