Yirmibeş Meral KARAOĞUZ, Mehmet Ali ERGÜN, Ece KONAÇ, Tuncay NAS, Sevda MENEVŞE

Cytogenetic evaluation of cordocentesis materials in the prenatal diagnosis and application of "Fish" as an additional technique

Amaç: Bu çalışmanın amacı kord kanı örneklerinin sitogenetik sonuçlarının değerlendirilmesi ve "sitogenetik olarak 46,XX" tesbit edilen olgularda floresan insitu hibridizasyon tekniği (FISH) uygulaması ile karyotipin doğrulanmasının sağlaması veya Y kromozomuna ait komponentin varlığının gösterilmesidir. Metodlar: Prenatal tanı amaçlı 111 kord kam kültüre edildi. "Karyotipi 46.XX" olan 66 olgunun, 20'sine X (DXZ1) ve Y (DYZ3) kromozomlarına ait a -satellit problar ile FISH tekniği uygulandı.Bulgular: Toplam 111 olgunun 106'sında (%95.4) karyotip normal iken, 5 (%4.5) olguda anomali belirlendi ( ikiregüler, bir mozaik trizomi 21, bir X kromozom mozaisizmi bir de 9. kromozomda perisentrik inversiyon). Karyotipi "46.XX" olan 20 olgudan bir tanesinde, analiz edilen 500 hücrenin 194'ünde (%20.8) hem X kromozomuna ait, hem de Y kromozomuna ait sinyal izlenmiştir. Sonuç: Sonuç olarak kord kan örneklerinde anomalili veya 46,XY karyotipinin belirlenmesi sonucun güvenilir olduğunu düşündürmesine karşın, "46,XX" karyotiplerinde sitogenetik değerlendirmenin doğruluğunun teyidi için FISH gibi ek bir tekniğin uygulanması gerekmektedir.

Kordosentez materyalinin prenatal tanı amaçlı sitogenetik değerlendirilmesi ve ek bir teknik olarak FISH uygulaması

Purpose: To evaluate the cytogenetic results of cord blood samples and apply fluorescence in situ hybridization (FISH) as an additional technique to "46,XX cytogenetically diagnosed cases" in order to confirm the karyotypes or to verify the occurrence of a Y chromosome component. Methods: 111 cord blood specimens were cultured for prenatal karyotyping. Of the 66 "46.XX kartoyped" materials, 20 of them were painted with X (DXZ1) and Y (DYZ3) chromosome ?-satellite probes by FISH. Results: Of the HI cases, 106(95.5%) were karyotypically normal, and 5 (4.5%) were abnormal (two regular and one mosaic trisomy 21, one X mosaidsm and one pericentric inversion of chromosome 9). In one of the 20 "46.XX" karyotyped cord blood specimens, 104 of 500 cells (20.8%) revealed one X signal and one Y signal. Conclusion: The evaluation of abnormal and 46, XY karyotypes in cord blood samples gave accurate results but "46,XX" karyotypes must be confirmed with an additional, technique like FISH for an accurate cytogenetic evaluation of specimens.

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