Consanguineous Marriages: Genetic Approach

Abstract

Consanguineous marriages (AE) are common in many parts of the world, and the risk of some rare congenital anomalies and recessive Mendelian diseases is increased in AE children due to the increase in identical homozygous regions. In AE studies, it has been reported that AE causes an increase in the risk of prenatal and perinatal losses and death in infancy and early childhood. In studies investigating the relationship between AE and multifactorial inherited diseases such as cancer, diabetes, hypertension, cardiovascular diseases, and some autoimmune disorders, the results have been inconsistent. Genetic counseling in AE couples provides valuable guidance in determining the carrier status and estimating the risk for the offspring. The aim of this review is to examine the relationship between AE and the etiology of diseases according to inheritance patterns and to emphasize the important role of genetic counseling in this practice.

Keywords

• consanguineous marriage
• autosomal recessive inheritance
• multifactorial inheritance
• genetic counseling
• carrier status

Akraba Evlilikleri: Genetik Yaklaşım

Abstract

Akraba bireyler arasındaki evlilikler (AE), dünyanın birçok bölgesinde yaygın olarak görülmekte olup, AE çocuklarında özdeş homozigotluk bölgelerinin artmış olması nedeniyle bazı nadir görülen konjenital anomaliler ile çekinik Mendelyen hastalıkların riski yükselmiştir. AE çalışmalarında, AE’nin prenatal ve perinatal kayıplar ile bebeklik ve erken çocukluk dönem ölüm riskinde artışa neden olduğu bildirilmiştir. Kanser, diyabet, hipertansiyon, kardiyovasküler hastalıklar, bazı otoimmün bozukluklar gibi multifaktöriyel kalıtılan hastalıklar ile AE ilişkisinin araştırıldığı çalışmalarda ise sonuçlar tutarsız bulunmuştur. AE çiftlerinde genetik danışmanlık, taşıyıcılık durumunun tespitinde ve yavrular için risk tahmininde değerli bir rehberlik sunmaktadır. Bu derlemenin amacı, AE ve kalıtım modellerine göre hastalıkların etiyolojisi ilişkisinin irdelenmesi ve genetik danışmanlığın bu uygulamadaki önemli rolünün vurgulanmasıdır.

Keywords

• akraba evliliği
• otozomal resesif kalıtım
• multifaktöryel kalıtım
• genetik danışmanlık
• taşıyıcılık

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