Ordering Recommendation

Carrier screening for cystic fibrosis (CF), fragile X syndrome (FXS), and spinal muscular atrophy (SMA) in women who are pregnant or planning a pregnancy. Not recommended for men, as FXS carrier screening is not indicated. Do not use for diagnostic testing in patients with symptoms of CF, FXS or SMA. For CF carrier screening alone, refer to Cystic Fibrosis (CFTR) Expanded Variant Panel (2013661). For SMA carrier screening alone, refer to Spinal Muscular Atrophy (SMA) Copy Number Analysis (2013436). For FXS carrier screening alone, refer to Fragile X (FMR1) with Reflex to Methylation Analysis (2009033).

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Lavender (K2EDTA). Also acceptable: Pink (K2EDTA).

Specimen Preparation

Transport 5 mL whole blood. (Min: 3 mL)

Storage/Transport Temperature


Unacceptable Conditions

Plasma or serum. Specimens collected in sodium heparin, yellow (ACD solution A), or lithium heparin tubes. Frozen specimens in glass collection tubes.


Ambient: 72 hours; Refrigerated: 1 week; Frozen: unacceptable


Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) Mass Spectrometry/Polymerase Chain Reaction (PCR)/Capillary Electrophoresis/Multiplex Ligation-Dependent Probe Amplification (MLPA)




4-14 days

Reference Interval

By report

Interpretive Data

Refer to report.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Compliance Category

Laboratory Developed Test (LDT)


Cystic Fibrosis (CF): The Cystic Fibrosis (CFTR) Expanded Variant Panel includes the 23 pathogenic CF variants recommended by the American College of Medical Genetics for population carrier screening as well as many others.

Fragile X:  If a CGG repeat of 100 or greater is detected by PCR and capillary electrophoresis; methylation analysis will be added. Additional charges apply.

Hotline History


CPT Codes

81220; 81329; 81243; if reflexed, add 81244


Component Test Code* Component Chart Name LOINC
0050556 Fragile X Allele 1 45321-7
0050558 Fragile X Allele 2 45322-5
0050559 Fragile X Methylation Pattern 41107-4
0050579 Fragile X Interpretation 36913-2
2001310 FRAG X Specimen 66746-9
2013437 SMA Copy Number, Specimen 31208-2
2013438 SMA Copy Number, Symptoms 75325-1
2013439 SMA Copy Number, SMN1 Copies 35462-1
2013440 SMA Copy Number, SMN2 Copies 54449-4
2013441 SMA Copy Number, Linked Variant 82155-3
2013442 SMA Copy Number, Int 49857-6
2013675 Cystic Fibrosis, Allele 1 42938-1
2013676 Cystic Fibrosis, Allele 2 42939-9
2013677 CF Expanded Variant Panel Interp 21656-4
2013692 Cystic Fibrosis 5T Variant 21654-9
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • CF
  • CFTR
Genetic Carrier Screen, (CF, FXS, and SMA) with Reflex to Methylation