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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Fragile X DNA Analysis, Fetus
Test Code16300
CPT Codes
81243<br><br data-cke-filler="true">
Physician Attestation of Informed Consent
This germline genetic test requires physician attestation that patient consent has been received if ordering medical facility is located in AK, DE, FL, GA, IA, MA, MN, NV, NJ, NY, OR, SD or VT or test is performed in MA.
Preferred Specimen
10 mL amniotic fluid collected in a sterile plastic leak-proof container
Minimum Volume
10 mL amniotic fluid • 10 mg dissected chorionic villus biopsy
Other Acceptable Specimens
10 mg chorionic villi collected in a sterile tube filled with sterile culture media, or cultured cells collected in (x2) sterile T-25 flasks, 75% confluent
Instructions
Do not hold specimen; forward to laboratory when specimen arrives.
For fetal testing:
1) Please call 1-866-GENE-INFO (1-866-436-3463) prior to submission
2) Documentation of parental carrier status must be provided
3) It is required that maternal cell contamination study, STR analysis be ordered in conjunction with fetal testing. A separate tube of maternal blood (EDTA) is required for this test.
Amniotic fluid: Normal collection procedure. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.
Amniocyte or chorionic villus (CVS) culture: Two sterile T25 flasks, 75% confluent, filled with culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when cells arrive.
Dissected chorionic villus (CVS) biopsy: 10-20 mg dissected chorionic villi collected in a sterile tube, filled with sterile culture media. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.
Note: Do not reject. Forward to performing laboratory for evaluation of sample.
For fetal testing:
1) Please call 1-866-GENE-INFO (1-866-436-3463) prior to submission
2) Documentation of parental carrier status must be provided
3) It is required that maternal cell contamination study, STR analysis be ordered in conjunction with fetal testing. A separate tube of maternal blood (EDTA) is required for this test.
Amniotic fluid: Normal collection procedure. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.
Amniocyte or chorionic villus (CVS) culture: Two sterile T25 flasks, 75% confluent, filled with culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when cells arrive.
Dissected chorionic villus (CVS) biopsy: 10-20 mg dissected chorionic villi collected in a sterile tube, filled with sterile culture media. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.
Note: Do not reject. Forward to performing laboratory for evaluation of sample.
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 48 hours
Refrigerated: Unacceptable
Frozen: Unacceptable
Refrigerated: Unacceptable
Frozen: Unacceptable
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Do not reject
Methodology
FX-Polymerase Chain Reaction/Triplet-Primed Polymerase Chain Reaction followed by Methylation PCR Analysis
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Set up: Wed (set up as needed); Report available: 12 days (5 days for PCR and 7 days additional if reflex required)
Limitations
Rare mutations in FMR1 gene unrelated to trinucleotide expansion will not be detected.
Reference Range
See Laboratory Report
Clinical Significance
This test is to be used in the prenatal diagnosis of Fragile X (FX) syndrome in pregnancies where the mothers are identified carriers of gray zone (45-54), permutation (55-200), or full-mutation (>200) CGG repeat alleles. It can also be used in the prenatal diagnosis of fetuses whose siblings are affected with FX.