Huntington hastalığı tanısı almış hastalarda ve ailelerinde CAG trinükleotid tekrar sayılarının fragman analizi ile tespiti

Year 2019, Volume: 44 Issue: 2, 517 - 523, 30.06.2019

Davut Alptekin , Perçin Pazarcı Mehmet Ali Bereketoğlu Mehmet Ali Erkoç , Nermin Seda Ilgaz , Ümit Lüleyap

https://doi.org/10.17826/cumj.461390

Abstract

Amaç: Huntington Hastalığı (HD), sinir sistemini etkileyen otozomal dominant bir hastalıktır. Huntingtin genindeki CAG trinükleotit tekrarı (TNR) artışı hastalığa neden olur. Normal bireylerde 10-35 TNR bulunurken HD'de bu sayı 36-37'yi aşmaktadır. Bu çalışmada, HD tanılı ailede TNR sayılarının araştırılması ve anormal alleli olan bireyler için genetik danışmanlık yapılması amaçlanmıştır.

Gereç ve Yöntem: Örnekler, HD nedeniyle 60 yaşında ölen bir erkeğin aile üyelerinden oluşmaktadır. Rastgele seçilen 57 sağlıklı birey de kontrol için analiz edilmiştir. TNR sayıları fragman analizi ile belirlenmiştir.

Bulgular: Aile bireylerinin TNR sayıları 17, 21, 23, 25, 33, 36 ve 39 olarak belirlendi. Rastgele seçilmiş sağlıklı kişilerin TNR sayıları 26'nın altında bulundu. 33 ve 36 TNR'li bireyler risk grubu olarak kabul edildi. 39 TNR'li bireyler HD’ye sahip olarak kabul edildi.

Sonuç: Bazı deneklerin 39 TNR'si olduğundan, bu kişilerin hekim kontrolünde olması gerektiği vurgulanmıştır. Çocuk sahibi olmayı planlayanlara prenatal tanı önerilmektedir. Ek olarak, 33 ve 36 CAG trinükleotid tekrarı olan deneklerin, HD ile ilgili yeni nesilleri bilgilendirmeleri ve gelecekte kendilerinin de etkilenebilecekleri bildirilmektedir.

Keywords

Huntington hastalığı, Huntingtin geni, Nörodejeneratif hastalıklar, Trinükleotid tekrarları

Detection of CAG trinucleotide repeat numbers with fragment analysis in patients diagnosed with Huntington’s disease and in their families

Abstract

Purpose: Huntington's Disease (HD) is an autosomal dominant disorder affecting nervous system. CAG trinucleotide repeat (TNR) increase in Huntingtin gene causes the disease. In normal individuals, 10-35 TNRs are found whereas in HD this number exceeds 36-37. This study aimed to investigate TNR numbers in individuals with HD diagnosed family and to provide genetic counselling for individuals with abnormal alleles.

Materials and Methods: Subjects consist of family members of a male who died at age of 60 due to HD. Randomly selected 57 healthy individuals are also analysed for control. TNR numbers were determined by fragment analysis.

Results: TNR numbers of family members were determined as 17, 21, 23, 25, 33, 36 and 39. TNR numbers of randomly selected healthy people were found below 26. Individuals with 33 and 36 TNRs were considered as risk groups. Individuals with 39 TNRs were considered as HD patients.

Conclusion: Since some subjects had 39 TNRs, it was emphasized that these people should be under physician control. Prenatal diagnosis is recommended to those who plan to have children. In addition, subjects with 33 and 36 CAG trinucleotide repeats are advised to inform new generations about HD and that they may be affected in future.

Keywords

Huntington's disease, Huntingtin gene, Neurodegenerative diseases, Trinucleotide Repeats

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