OTİZMİN GENETİK TEMELLLERİ

Öz

Otistik bozukluk toplumsal ve iletişimsel sorunları yaşamları boyunca süren çocukları ve erişkinleri içine alan, özellikle erkeklerde (4:1) daha sık görülen yaygın gelişimsel bir bozukluktur. Yineleyici-sınırlayıcı hareketler dışında iletişim ve bilişsel gelişimde gecikme ya da sapma ile karakterizedir. Otizm etiyolojisinin bilinmemesine rağmen yapılan çalışmalar hastalığın oluşmasında genetik faktörlerin büyük rol oynadığını göstermiştir. Otistik çocukların kardeşlerinde otizm görülme riskinin sağlıklı bireylerin kardeşlerinden 30-150 kat yüksek olduğu tespit edilmiştir. Otizm üzerindeki son dönem araştırmalar genetik, beyin işlevleri, nörokimyasal ve immünolojik etkenler üzerine yoğunlaşmıştır. Bağlantı ve ilişki çalışmaları ile belirli kromozom bölgelerinde (2, 3, 7, 11, 15, 17, X kromozomları) anlamlı sonuçlar bulunmuştur. Otizm için bilinmeyenlerin ışığında ayırıcı tanıda yol gösterebilecek, tedaviye yanıtı öngörebilecek veya ölçebilecek biyolojik belirteçler saptanmasının önemi büyüktür. Bu derleme otizmin genetik kökeni hakkında kısa bir özet verilmesi ve otizme sebep olabileceği düşünülen genetik faktörlerin gözden geçirilmesi amacıyla yazılmıştır

Anahtar Kelimeler

• Otizm, yaygın gelişimsel bozukluk, genetik, bağlantı, kromozomal bozukluk

The Genetic Basis of Autism

Öz

Autistic spectrum disorder is a neuropsychiatric disorder which begins in the early years of life with delays and deviance in social, communicative and cognitive development and with restricted repertoire of activities and interests. Autism affects males four times more than females. Although the etiology of autism is unknown, evidence indicates that genetic factors play a major role in this disorder. The sibling recurrence risk of autism for additional children in families with an autistic child is 30-150 times greater than the population prevalence. Recent studies have focused on genetics, brain function, neurochemical and immunological factors. Significant results were found in several different chromosome regions (2, 3, 7, 11, 15, 17, X) with linkage and association studies. It is of great importance to detect biological markers for the differential diagnosis of autism. This review was written to give short information about the genetic basis of autism and for the revision of genetic factors thought to have a role in the etiology of autism

Anahtar Kelimeler

• Autism, autism spectrum disorders, genetics, linkage, chromosomal abnormalities

Kaynakça

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