Prenatal test for fetuses with ultrasound findings suggestive of CHARGE syndrome, or for individuals who had a previous child with CHARGE syndrome, but do not know the specific mutation.
- Patient Preparation
- Cultured Amniocytes: Four T-25 flasks at 80 percent confluent cultured amniocytes. If the client is unable to culture amniocytes, this can be arranged by contacting Client Services at (800) 522-2787.
Or Amniotic Fluid: Amniotic fluid submissions will require cultured amniocytes (Order Amniocyte Culture, Four Flask).
AND Maternal Whole Blood: Lavender (K2EDTA), Lavender (K3EDTA), Pink (K2EDTA), or Yellow (ACD Solution A or B).
- Specimen Preparation
- Cultured Amniocytes: Fill flask with culture media. Transport four T-25 flasks at 80 percent confluent of culture amniocytes filled with culture media.
Amniotic Fluid: Transport 10 mL unspun fluid (Min: 5 mL)
Maternal Whole Blood: Transport 3 mL whole blood (Min: 1 mL)
- Storage/Transport Temperature
- Cultured Amniocytes: CRITICAL ROOM TEMPERATURE. Must be received within 48 hours of shipment due to liability of cells.
Amniotic Fluid: Room temperature.
Maternal Whole Blood: Room temperature.
- Unacceptable Conditions
- Plasma or serum.
- Fetal Specimen: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Maternal Whole Blood: Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
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, 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 fetuses 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.
For quality assurance purposes, ARUP Laboratories will confirm the result at no charge following delivery. Order Confirmation of Fetal Testing and include a copy of the original fetal report (or the mother's name and date of birth) with the test submission. Please contact an ARUP genetic counselor at (800) 242-2787 extension 2141 prior to specimen submission.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|0050548||Maternal Contamination Study Fetal Spec||59266-7|
|0050612||Maternal Contam Study, Maternal Spec||31208-2|
|2012718||CHD7 FE Sequencing, Specimen||31208-2|
|2012719||CHD7 FE Sequencing, Interpretation||42240-2|