Recommended test to confirm a clinical diagnosis or suspected diagnosis of CHARGE syndrome.
Polymerase Chain Reaction/Sequencing
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 1 mL)
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Background Information for CHARGE Syndrome (CHD7) Sequencing:
Characteristics: CHARGE is an acronym for the major features of the condition, which are Coloboma, Heart defects, choanal Atresia, Restricted growth and delayed development, Genital abnormalities and Ear anomalies. This condition has a highly variable presentation.
Incidence: About 1 in 10,000.
Inheritance: Autosomal dominant.
Cause: Pathogenic CHD7 gene mutations.
Clinical Sensitivity: Approximately 90 percent for individuals fulfilling clinical criteria for CHARGE.
Methodology: Bidirectional sequencing of all coding regions and intron-exon boundaries of the CHD7 gene.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations, deep intronic mutations and large deletions/duplications in CHD7 will not be detected.
Laboratory Developed Test (LDT)
|Component Test Code*||Component Chart Name||LOINC|
|2012610||CHD7 FGS Sequencing Specimen|
|2012611||CHD7 FGS Sequencing Interpretation|