MYH9-Related Disorders, MYH9 Gene, Next-Generation Sequencing, Varies

Casandra

Casandra Test Code MC53644Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID GNMY9CPT Code 81479

MYH9-Related Disorders, MYH9 Gene, Next-Generation Sequencing, Varies

Clinical Use

Use

This test is essential for evaluating MYH9-related disorders such as May-Hegglin anomaly and Sebastian syndrome, especially in individuals with a family history suggestive of such disorders. It aids in diagnosing when phenotypic tests are inconclusive but clinical suspicion remains high, confirming diagnoses through the identification of known or suspected pathogenic alterations in the MYH9 gene. The test is pivotal for assessing disease-causing alterations to understand the underlying molecular defect in diagnosed patients and assisting in genetic counseling for familial screening.

Special Instructions

This test should not be used for prenatal diagnosis. It is critical for identifying disease-causing alterations within the MYH9 gene to guide prognosis, risk assessment based on genotype-phenotype correlations, and provide carrier testing for close family members. Documentation of informed consent is necessary for New York clients.

Limitations

The test is not designed for evaluating hereditary bleeding disorders outside of MYH9-related conditions. There are technical limitations in detecting all types of genomic variants, and the test might not identify low levels of mosaicism or differentiate between somatic and germline variants. Next-generation sequencing may have reduced sensitivity for certain target regions and may not cover all gene sections, as some regions of homology and high GC content may impede evaluation. Results may be inaccurate if the patient has had a recent hematopoietic stem cell transplant or blood transfusion due to the presence of donor DNA.

Test Details

New York Approved