Medical Genetics Test Details
View Custom Req | Tests in Custom Req: 0
|Proband Whole Exome Sequencing Plus CMA|
|Test Information:||The Proband Whole Exome Sequencing Plus CMA test is ordered by a physician and must be accompanied with a consent form and detailed clinical information. In general, the test is used when a patient's medical history and physical exam findings strongly suggest that there is an underlying genetic etiology. In some cases, the patient may have had an extensive evaluation consisting of multiple genetic tests, without identifying an etiology. In other cases, a physician may opt to order the Proband Whole Exome Sequencing Plus CMA test early in the patient's evaluation in an effort to expedite a possible diagnosis. See (Frequently Asked Questions (FAQ)) for additional details.
- Patient with undiagnosed genetic syndrome
This test has two components:
Component 1: Proband Whole Exome Sequencing (WES): the Proband Whole Exome Sequencing test is a highly complex test that is newly developed for the identification of changes in a patient's DNA that are causative or related to their medical concerns. In contrast to current sequencing tests that analyze one gene or small groups of related genes at a time, the Proband Whole Exome Sequencing test will analyze the exons or coding regions of thousands of genes simultaneously using next-generation sequencing techniques. The exome refers to the portion of the human genome that contains functionally important sequences of DNA that direct the body to make proteins essential for the body to function properly. These regions of DNA are referred to as exons. There are approximately 180,000 exons in the human genome which represents about 3% of the genome. These 180,000 exons are arranged in about 22,000 genes. It is known that most of the errors that occur in DNA sequences that then lead to genetic disorders are located in the exons. Therefore, sequencing of the exome is thought to be an efficient method of analyzing a patient's DNA to discover the genetic cause of diseases or disabilities. The principle of the test is to sequence nucleotide by nucleotide, the human exome of an individual to a depth of coverage necessary to build a consensus sequence with high accuracy. This consensus sequence is then compared to standards and references of what is normal in the population and the result is interpreted by board-certified laboratory directors and clinicians. By sequencing the exome of a patient and comparing it to normal reference sequence, variations in an individual's DNA sequence can be identified and related back to the individual's medical concerns in an effort to discover the cause of the medical disorder.
Component 2: Chromosomal Microarray Analysis - Comprehensive (CMA-Comprehensive) combines both CMA-HR and CMA-SNP into one array. The new 400k custom designed CMA-Comprehensive microarray (v10.1) now targets over 4,200 genes at the exon level. In addition to exon level copy number, this array also includes 60,000 probes used for SNP analysis for the detection of uniparental disomy (UPD) and absence of heterozygosity (AOH). The breakdown of the new targeted genes added is a follows:
41 clinically relevant genes that have been published in the last 24 months
742 genes that are available as a clinical test in the GeneTest database
804 X-linked genes
276 nuclear mitochondrial and candidate genes
232 autoimmune genes
316 OMIM autosomal dominant morbid genes
100 predicted haploinsufficient genes
153 genes associated with autism
186 candidate genes associated with epilepsy
44 genes associated with ADHD
These new genes are in addition to the previously 1,700 targeted genes associated with intellectual disability, seizure disorders, autism, heart defects, etc.
For more information on specific coverage, click here: Whole Exome Sequencing Version 3 Coverage Search Tool
|Methodology:||Exome Capture and Next Generation Sequencing, Microarray|
|Sample & Shipping Information|
|Test Requisition:||Proband Whole Exome Sequencing|
|Requirements:||Draw blood in both Sodium Heparin (green-top) tube(s) and an EDTA (purple-top) tube(s). Send at least send 3-5 cc (Adults/Children) for each tube.|
|Shipping Conditions:||Ship at room temperature in an insulated container by overnight courier. Do not heat or freeze. Sample must arrive within 48 hrs.
|Specimen Type:||Cultured Skin Fibroblast|
|Requirements:||Send 2 T25 flasks at 80-100% confluence.|
|Shipping Conditions:||Ship at room temperature in an insulated container by overnight courier. Do not heat or freeze.
|Turn Around Time:||14 days for CMA and 15 weeks for WES|
|List Price:||*For Insurance or Institutional Prices, please call.|
|CPT Codes:||81415x1, 81229x1|