The CEP X SpectrumOrange/Y SpectrumGreen DNA Probe Kit is intended to detect alpha satellite sequences in the centromere region of chromosome X and satellite III DNA at the Yq12 region of chromosome Y in conjunction with routine diagnostic cytogenetic testing. It is indicated for use as an adjunct to standard cytogenetic analysis for identifying and enumerating chromosomes X and Y via FISH in interphase nuclei and metaphase spreads obtained from bone marrow specimens in subjects who received opposite-sex bone marrow transplantation for chronic myelogenous leukemia (CML), acute myeloid leukemia (AML), myeloproliferative disorder (MPD), myelodysplastic syndrome (MDS), acute and lymphoid leukemia (ALL), or hematological disorder not otherwise specified (HDNOS). It is not intended to be used as a stand alone assay for test reporting; FISH results are intended to be reported and interpreted only in conjunction with results from standard cytogenetic analysis, performed concurrently, using the same patient specimen. This device is not intended for use in subjects with like-sex bone marrow transplants; with matrices other than unstimulated, cultured bone marrow specimens; or in screening for constitutional X and Y chromosome aneuploidies.
Limitations of the Procedure
- The CEP X/Y DNA Probe Kit has been optimized only for identifying chromosomes in interphase nuclei or metaphase spreads from bone marrow specimens.
- This assay identifies only the proportion of donor and recipient cells in bone marrow specimens from recipients of opposite-sex bone marrow transplantation. It does not distinguish between malignant and normal cells; it is not designed to detect structural or other chromosome abnormalities in malignant clones, which is possible with standard cytogenetics.
- The Y chromosome is sometimes lost in bone marrow cells of elderly males regardless of whether the specimen is from a donor, a recipient, or collected from a patient in the post-bone marrow transplantation period.
- It is important to have pretransplant cytogenetic results on both donor and recipient for the following reasons: (1) There are rare male patients who may have an unusual Y chromosome (lacking the Yq heterochromatic region) which cannot be identified with the CEP X/Y assay. (2) Some individuals may have target sequences at alternate chromosome locations that hybridize to the CEP X or Y probes. This has not been investigated for CEP X, however, chromosome polymorphisms which hybridize with the Y probe occur with a frequency of 1 in 2,000. Such cases may be detected by CEP X/Y metaphase analysis and sometimes by standard cytogenetic analysis. (3) Constitutional sex chromosome aneuploidy, including mosaicism, present in either donor or recipient can complicate signal enumeration and test interpretation.
- In a male donor or recipient with a 46, XY, - Y, + X karyotype, a certain percentage of cells with XX signals will be detected by CEP X/Y.
- If significant peripheral blood contamination is present in the bone marrow specimen, the blood may dilute the specimen. It is important to recognize the potential effects this dilution effect may have on the FISH assay results; dilution of the bone marrow with blood may alter the donor:recipient cell ratio.
- The CEP X/Y assay has been validated only for use with unstimulated, cultured bone marrow specimens obtained from recipients of opposite-sex BMT. It is not intended for chromosome X and Y enumeration in other patient populations or with other test matrices such as amniocytes, chorionic villi, fibroblasts, tumor cells, long term cultures, among others.
- FISH assay results may not be informative if the specimen quality and/or specimen slide preparation is inadequate.
- This device is not intended for use in subjects with like-sex bone marrow transplants or for use in diagnostic testing or screening for constitutional X and Y chromosome aneuploidies.
- Residual fetal cells may potentially exist in either donor or recipient cells, however the levels at which these cells exist is likely to be below the levels of detection of both standard cytogenetics and FISH.
- The CEP X/Y assay has not been validated for monitoring engraftment status.
- The clinical significance and interpretation of FISH results should be made in conjunction with proper controls, standard cytogenetic analysis, and within the context of the patient’s medical history and other clinical findings.
Warnings and Precautions
- For In Vitro Diagnostic Use
- The ProbeChek Control Slides to be used with this kit are manufactured from human cultured lymphoblast cells that have been fixed multiple times in a solution of methanol:acetic acid (3:1). Because it is often impossible to know which might be infectious, all human specimens and control slides should be treated with universal precautions. Guidelines for specimen handling are available from the US Centers for Disease Control and Prevention.
- Hybridization conditions may be adversely affected by the use of reagents other than those provided or recommended by Abbott Molecular.
- Failure to follow all procedures for slide denaturation, hybridization and signal enumeration may cause unacceptable or erroneous results.
- Fluorophores are readily photobleached by exposure to light. To limit this degradation, handle all solutions containing fluorophores in reduced light. This includes all steps involved in handling the hybridized slide. Carry out all steps which do not require light for manipulation (incubation periods, washes, etc.) in subdued lighting to avoid direct light projecting onto the fluorophore.
- CEP X/Y DNA Probe contains formamide, a teratogen. Avoid contact with skin and mucous membranes. Refer to MSDS for more information.
- The use of a calibrated thermometer is strongly recommended for measuring temperatures of solutions, waterbaths, and incubators as these temperatures are critical for optimum product performance.
- All hazardous materials should be disposed of according to your institution’s guidelines for hazardous disposal.