Ayşegül TÜRKYILMAZ, Diclehan ORAL, SELDA ŞİMŞEK, Turgay BUDAK

De Novo dengeli 18pter delesyonlu olgu sunumu

Bu çalışmamızda, Anabilim dalı laboratuvarımıza gönderilen, öyküsünde kötü obstetrik anemnez bulunan aileye yapılan sitogenetik ve moleküler sitogenetik (FISH) analiz sonuçları sunulmuştur. Erkekte normal karyotip (46,XY), fenotip olarak normal gözüken kadında ise 46,XX,der(18;22)(18pter→p11.1::22p11.1→qter)del(18) (:p11.1→qter) kromozom kuruluşu saptanmıştır. Bu translokasyonun orijinini belirlemek amacıyla probandımızın ulaşılan akrabalarından anne ve babasının sitogenetik incelenmesinde her iki ebeveyninde normal olduğu gözlemlenmiş ve olgunun de novo olduğuna karar verilmiştir. Bu taşıyıcı bireylerin öykülerindeki tekrarlayan anomalilerin, gamet oluşumu sırasındaki translokasyonun dengesiz dağılımı sonucu olabileceği düşünülmüş ve sonraki tüm gebeliklerinde prenatal sitogenetik tanı önerilmiştir.

A case with deletion of De Novo balanced 18pter

In this study, we are presenting the results of cytogenetic analysis and molecular cytogenetic analysis (FISH) of the couple and their family, who were referred to our genetic diagnostic laboratory and had bad obstetrics history. We found a normal karyotype (46,XY) in male, and A de novo complex chromosome rearrangement found in a phenotypically normal female was characterized by G-bands, FISH with probes. Her chromosome structure was 46,XX,der(18;22)(18pter→p11.1::22p11.1→qter) del(18)(:p11.1→qter). To determine the parental origin of translocation, we examined the individuals of the family, and we found that the translocation was de novo. We concluded that this carrier family might be due to the unbalanced distribution of translocation, during gamete formation and prenatal diagnosis recommended for their future pregnancies.

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