Cytogenetic and Molecular Evaluation of Ambiguous Genitalia In Pediatric Patients

Abstract

Objective: A newborn with ambiguous genitalia needs prompt evaluation to detect life-threatening conditions such as salt-losing crisis in congenital adrenal hyperplasia (CAH) and gender assignment. Sex assignment in these newborn continues to be a challenging diagnostic and therapeutic problem. In our study, we aimed to investigate the causes and characteristics of ambiguous genitalia in 21 newborn who were referred to a cytogenetic laboratory. Materials and Methods: Cytogenetic analysis was performed for each case. The cases were analysed by also molecular genetic and interphase FISH technique to exhibit exist Y. Chromosome molecular genetic analysis was performed for Y chromosomal loci (SRY, ZFY, SY84, SY86, SY127, SY134, SY254, SY255). Genomic DNA was extracted from peripheral blood. Results: In all of patient were detected 46,XX and 46,XY karyotype by cytogenetic analysis. 21 cases were successfully analyzed by interphase-FISH. Some individuals carry a Y chromosome but are phenotypically female or one of cases have a female karyotype but are phenotypically male. Conclusion: The correlation between genotype (SRY+/-) and phenotype is still unclear. The etiology of ambiguous genitalia is variable. The physician managing these families could minimize the trauma of having a child with unidentified sex by providing appropriate genetic counseling so that the parents can make an early decision. ©2008, Firat University, Medical Faculty

Keywords

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Pediatrik Hastalarda Ambigious Genitalyanın Sitogenetik ve Moleküler Değerlendirmesi

Öz

Amaç: Ambigious genitalyalı yeni doğanın, cinsiyet belirlenmesi ve konjenital adrenal hiperplazide (KAH) tuz kaybetme krizi gibi yaşamı tehlikeye sokan durumların tespit edilmesi için değerlendirilmesi gerekir. Bu yeni doğanlarda cinsiyet belirlenmesi, tanı koyma ve tedaviyle ilgili problemlerin üstesinden gelmeyi sağlar. Bu çalışmamızda, sitogenetik laboratuarına gönderilen 21 yeni doğanda ambigious genitalyanın özellikleri ve bu duruma yol açan nedenleri araştırmayı amaçladık. Gereç ve Yöntem: Her bir vaka için sitogenetik analiz yapıldı. Y kromozomunun varlığını göstermek için vakalar moleküler genetik ve interfaz FISH tekniğiyle analiz edildi. Y kromozom bölgeleri (SRY, ZFY, SY84, SY86, SY127, SY134, SY254, SY255) için moleküler genetik analiz yapıldı. Genomik DNA periferik kandan izole edildi. Bulgular: Hastaların hepsinde sitogenetik analizle 46,XX ve 46,XY karyotipi tespit edildi. 21 olgu interfaz FISH tekniğiyle başarılı bir şekilde analiz edildi. Bazı bireyler Y kromozomu taşımaktadır ama fenotipik olarak dişidir ya da bir olgu dişi karyotipe sahiptir ama fenotipik olarak erkektir. Genotip (SRY+/-) ve fenotip arasındaki korelasyon hala net değildir. Sonuç: Ambigious genitalyanın etiyolojisi değişkenlik göstermektedir. Hekimlerin, ebeveynlere erken karar verebilmesi açısından uygun genetik danışmanlık vermesiyle cinsiyet belirsizliği bir çocuğa sahip olma travmasını hafifletebilir. ©2008, Fırat Üniversitesi, Tıp Fakültesi

Anahtar Kelimeler

• Ambigious genitalya, SRY, sitogenetik analiz, interseks bozukluklar

Kaynakça

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