PRENATAL TANIDA MİKRODİZİNİN ROLÜ

Öz

Prenatal genetik tanı 1960’lardan beri yapılabilmekle birlikte, 1980 sonrasında yaygın olarak kullanılmaya başlanmıştır. Sitogenetik inceleme, bölünebilir hücre ve hücre kültürü gereksinimi, düşük ayrım gücü (<4-5Mb) ve sübjektif değerlendirme gibi dezavantajlara sahiptir. Bu sorunların üstesinden gelme umuduyla prenatal mikrodizin incelemesinin kullanımı yaygınlaşmaya başlamış, ancak kendine has başka sorunlar nedeniyle henüz konvansiyonel sitogenetiğin yerini almamıştır. Yüksek ayrım gücüne sahip olması, objektif bir değerlendirme sunması ve bölünen hücreye gerek duymaması mikrodizinin avantajlarını oluştururken; etkisi tam olarak bilinemeyen değişimleri de saptaması ve buna bağlı olarak parental anksiyeteye yol açabilmesi ise dezavantajları arasında yer almaktadır. Ülkeler arasında prenatal kullanımdaki önceliği değişmekle birlikte hepsinde ortak görüş, ultrasonografide yapısal anomalisi olan fetüslerin ve düşük materyallerinin genetik incelemesinde ilk tercih olduğudur.

Anahtar Kelimeler

• mikrodizin
• prenatal
• genetik

The Role of Microarray in Prenatal Diagnosis

Öz

Although prenatal genetic diagnosis has been in use since the 1960s, it has been widely used after 1980s. The need for divisible cells and cell culture, low discrimination power (<4-5Mb) and subjective evaluation are the disadvantages of cytogenetic analysis. The use of prenatal microarray analysis has been becoming widespread in the hope of overcoming these problems, but has not yet replaced conventional cytogenetics due to its own disadvantages. While having high discrimination power, providing an objective evaluation and not needing dividing cells constitute its advantages; its high discrimination power is also a disadvantage, because of variants of unsignificance and incidental findings that can cause parental anxiety. Although the indications of prenatal use varies among countries, the common point is that prenatal microarray analysis is the first choice in the genetic examination of fetuses with structural anomalies detected prenatally and of intrauterin fetal demise.

Anahtar Kelimeler

• microarray
• prenatal
• genetic

Kaynakça

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