Test Directory

Test Code
22Q
Test Name
Noninvasive Prenatal Aneuploidy Screening for 22q11.2 Microdeletion
CPT Codes
81422
Expected Turnaround Time
4-6 days
Clinical Utility

Noninvasive prenatal screening to identify 22q11.2 deletion syndrome, also known as DiGeorge syndrome. Early detection allows for immediate intervention, specialized care, and prenatal management of issues like congenital heart defects, immunodeficiency, hypocalcemia, and developmental delays.

Specimen and Container Info

Specimen: Whole Blood

Collection Container: Streck Cell-Free BCT

Specimen Volume: 7-10 mL

*For Add-on requests:

  • contact Genomics for add-on approval
  • Genomics does not place add-on orders
Collection Instructions
  1. Collect two Streck Cell-Free tubes. Note: If ordered with standard Cell-Free DNA (NIPT), no additional tubes need to be collected.
  2. Draw blood using Vacutainer system (butterfly not appropriate); invert tube 10 times.
  3. Specimen must be collected at or greater than 10 weeks gestational age.
  4. *For Add-on requests:
  • contact Genomics for add-on approval
  • Genomics does not place add-on orders
Transport Instructions
  • Transport at room temperature.
  • Do not freeze or expose to extreme temperatures.
Stability Requirements

Room Temperature

5 days

*For Add-on requests:

  • contact Genomics for add-on approval
  • Genomics does not place add-on orders

Refrigerated

*For Add-on requests:

  • contact Genomics for add-on approval
  • Genomics does not place add-on orders

Frozen

*For Add-on requests:

  • contact Genomics for add-on approval
  • Genomics does not place add-on orders

Freeze/Thaw Cycles

*For Add-on requests:

  • contact Genomics for add-on approval
  • Genomics does not place add-on orders
Causes for Rejection
  • Specimen collected at <10 weeks gestation
  • Twin pregnancy
  • Improperly labeled specimen (minimum of two patient identifiers)
  • Inappropriate specimen type
  • Incomplete or incorrect test request form
  • Insufficient volume
  • Specimen has leaked in transit
  • Specimen without a test order
Methodology
Next Generation Sequencing of Cell-Free DNA
Performing Location
Genomics - Snowdrift
Alternate Names
  • 22q deletion
  • 22q11.2 deletion
  • DiGeorge
  • Fetal 22q11.2
  • Microdeletion
  • VCFS
  • Velocardiofacial syndrome
  • NIPT
  • NIPS
  • cfDNA
  • Cell Free DNA Screening
Description

Noninvasive prenatal screening using cell-free DNA testing is currently the most sensitive and specific screening test for common fetal aneuploidies involving chromosomes 21, 18, 13, X, and Y with optional fetal sex detection and 22q microdeletion screening. This test can be completed as early as 10 weeks gestational age. NIPS can provide expecting mothers the knowledge needed to make medical decisions regarding pregnancy, including the decision to pursue more invasive testing methods. NIPS is the best option for expecting patients to predict the likelihood of certain chromosome aneuploidies such as Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), and Patau syndrome (trisomy 13), and sex chromosome aneuploidies. NIPS can also predict the likelihood of 22q microdeletion syndrome, a condition caused by a small missing piece on chromosome 22. NIPS is now endorsed by the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine for all patients, regardless of maternal age. This test is suitable for singleton and twin pregnancies and IVF with egg donor pregnancies (singleton and twin).

Testing Schedule
Routine, at least twice per week