Test Details
Methodology
DNA analysis by polymerase chain reaction (PCR)
Result Turnaround Time
3 - 7 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
Provide evidence that twins are monozygotic versus dizygotic. This test may be used for legal purposes, obstetric management, as part of a transplant evaluation, and for other purposes.
Special Instructions
Include race/ethnicity and gender of the twins. Samples being tested at the request of a clinical account must have a completed test request form. If this study is collected for legal purposes, appointments and paternity kits are required. Specimens for legal testing must be collected with chain-of-custody paper work. To receive a complete paternity kit, blood or buccal swab, or for an appointment for legal testing, telephone 800-742-3844.
Limitations
The probability that twins are monozygotic is a statistical assessment and, as such, even though the twins have identical results and a high probability of being monozygotic, there is always a small probability that the twins are dizygotic. This chance is reflected in the probability provided. The statistical assessment can be improved by the submission of the parents of the twins.
This test was developed, and its performance characteristics determined, by LabCorp. This test has not been cleared or approved by the US Food and Drug Administration (FDA). The FDA has determined that such clearance is not necessary.
References
Specimen Requirements
Specimen
Whole blood or buccal swabs; other samples, such as amniotic fluid, cultured cells, and tissue specimens, may be used.
Volume
3 mL whole blood or four buccal swabs; other tissue as available.
Container
Lavender-top (EDTA) tube or four buccal swabs in a sealed envelope (buccal swab kit). Amniotic fluid and tissue in appropriate transport container. When submitting buccal swabs, please use a buccal swab kit provided by LabCorp. To obtain the buccal swab kit, please telephone 800-533-1037.
Reference Range
If the twins do not have identical results, the report will conclude the twins are dizygotic. If the twins have identical results, a statistical assessment of the probability they are monozygotic is provided. The monozygotic probability assessment will typically exceed 99.0%.
Storage Instructions
Maintain blood specimen at room temperature and keep dry.
Causes for Rejection
Improperly labeled specimen; improperly filled out client authorization/chain-of-custody form; insufficient amount of DNA on buccal swabs
LOINC® Map
Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
---|---|---|---|---|---|---|
176548 | Twin Zygosity Study | 176530 | D3S1358 | N/A | ||
176548 | Twin Zygosity Study | 176531 | D7S820 | N/A | ||
176548 | Twin Zygosity Study | 176532 | Amelogenin | N/A | ||
176548 | Twin Zygosity Study | 176533 | vWA | N/A | ||
176548 | Twin Zygosity Study | 176534 | FGA | N/A | ||
176548 | Twin Zygosity Study | 176535 | D8S1179 | N/A | ||
176548 | Twin Zygosity Study | 176536 | D21S11 | N/A | ||
176548 | Twin Zygosity Study | 176594 | D18S51 | N/A | ||
176548 | Twin Zygosity Study | 176595 | D5S818 | N/A | ||
176548 | Twin Zygosity Study | 176596 | D13S317 | N/A | ||
176548 | Twin Zygosity Study | 176597 | D16S539 | N/A | ||
176548 | Twin Zygosity Study | 176598 | TH01 | N/A | ||
176548 | Twin Zygosity Study | 176599 | TPOX | N/A | ||
176548 | Twin Zygosity Study | 176600 | CSF1PO | N/A | ||
176548 | Twin Zygosity Study | 176603 | QC | N/A | ||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176530 | |||||
Result Code Name | D3S1358 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176531 | |||||
Result Code Name | D7S820 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176532 | |||||
Result Code Name | Amelogenin | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176533 | |||||
Result Code Name | vWA | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176534 | |||||
Result Code Name | FGA | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176535 | |||||
Result Code Name | D8S1179 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176536 | |||||
Result Code Name | D21S11 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176594 | |||||
Result Code Name | D18S51 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176595 | |||||
Result Code Name | D5S818 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176596 | |||||
Result Code Name | D13S317 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176597 | |||||
Result Code Name | D16S539 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176598 | |||||
Result Code Name | TH01 | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176599 | |||||
Result Code Name | TPOX | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176600 | |||||
Result Code Name | CSF1PO | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 176548 | |||||
Order Code Name | Twin Zygosity Study | |||||
Order Loinc | ||||||
Result Code | 176603 | |||||
Result Code Name | QC | |||||
UofM | ||||||
Result LOINC | N/A |