Elif Funda ŞENER, Gökmen ZARARSIZ, Keziban KORKMAZ, Didem Behice ÖZTOP, Yusuf ÖZKUL

Otistik spektrum bozukluklarında SLC6A4 geni ekspresyonunun araştırılması

Amaç: Otizm kompleks bir nörogelişimsel bozukluk olarak tanımlanmaktadır. Hastalık etiyolojisinde genetik bir taban olduğu bilinmektedir. Serotonin ve otizm arasında bir ilişki olduğu daha önce yapılan çeşitli araştırmalarla gösterilmiştir. SLC6A4 geni (SERT veya 5-HTT) serotoninin geri alımında önemli bir role sahiptir. Bu özelliğinden dolayı bu çalışmada otizm hastalarında SLC6A4 geninin ekspresyon düzeyi araştırılmıştır. Yöntemler: Erciyes Üniversitesi Tıp Fakültesi Çocuk ve Ergen Ruh Sağlığı ve Hastalıkları Anabilim Dalı'na ilk kez başvurup, yapılan değerlendirme sonrası DSM-V kriterlerine göre otistik spektrum bozukluğu (OSB) tanısı alan 34 hasta (26 erkek, 8 kız) ve sağlıklı 23 kontrol (16 erkek, 7 kız) çalışmaya dahil edilmiştir. Gruplardan alınan periferal kan örneklerinden TRIzol yardımıyla RNA izolasyonu yapılmıştır. SLC6A4 geni ekspresyonu Kantitatif Real-Time PCR (qRT-PCR) ile belirlenmiştir. Bulgular: SLC6A4 geni ekspresyonunun hasta grubunda kontrol grubuna göre istatistiksel olarak önemli ölçüde daha düşük olduğu bulundu (p=0,027). Sonuç: Hasta grubunda ekspresyonun düşük olması serotoninin geri alınımında bir bozukluk olduğunu düşündürmektedir. Elde edilen bu sonuçlarımıza göre genin ekspresyonunun aynı hasta grubunda genişletilerek çalışılması, özellikle genin metilasyon durumu ve genin ekspresyonunu etkileyen polimorfizmlerin de birlikte araştırılması gerektiği düşünülmektedir.

Investigation of SLC6A4 gene expression in autism spectrum disorders

Objective: Autism is defined as a complex neurodevelopmental disorder. Genetics plays a major role in the etiology of autism spectrum disorders (ASD). The role of the serotonin in the development of autism has been widely investigated. SLC6A4 gene (SERT or 5-HT) has an important role reuptaking of serotonin. Because of this, our study examined the expression level of SLC6A4 gene in autism patients. Methods: Thirty-four patients (26 male, 8 female) who diagnosed as autism firstly according to DSM-V criteria in the Department of child psychiatry, Erciyes University Medical Faculty and healthy 23 controls (16 male, 7 female) were enrolled in this study. Total RNA was isolated from peripheral blood samples using TRIzol. Quantitative Real-time PCR (qRT-PCR) was performed to detect SLC6A4 gene expression. Results: SLC6A4 gene expression was found statistically significant and low in autism group compared with controls (p=0,027). Conclusion: The low gene expression in the patient group implied that there is an abnormality of serotonin reuptake. According to our results, we suggest that much more studies may be planned with the expression and methylation profile of this gene combined with gene polymorphisms especially affecting the expression in larger sample sizes. J Clin Exp Invest 2015; 6 (2): 165-169.

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