Estimation of Heritability and Inheritance of Some Human Traits and Diseases

Öz

Population genetics relies heavily on mathematical modeling to make quantitative predictions about the behavior of genes in populations. These models are based on Mendel's classical gene inheritance principles, the Hardy-Weinberg balance law that predicts gene frequency in a population, and Darwin's theory of natural selection. In recent years, studies using genome-wide data on the prediction of human traits and disease inheritance (ℎ2) are quite common. The majority of results from studies using twins have shown that all of the human complex features are inherited. Heredity grade is measured as either the contribution of total genetic variation (broad sense heredity) or additive genetic variation (narrow sense heredity). Various methods have been proposed to estimate the heritability of features and diseases. The heritability of a feature refers to the rate of phenotypic variation resulting from genetic variation among individuals. It provides important information about the genetic basis of complex features and indicates whether a phenotype is a suitable target for more specific statistical and molecular genetic analysis. However, the degree of heredity is not a constant feature of a phenotype, and may vary with population-specific differences in genetic background and environmental variation. The aim of this study is to introduce three different methods commonly used to estimate the degree of heredity. 

Anahtar Kelimeler

• Population,genetics,heredity,human,disease

Kalıtım Derecesinin Tahmini ve İnsan Hastalıkları İle Bazı Özelliklerinin Kalıtsallığı

Öz

Popülasyon genetiği, popülasyonlardaki genlerin davranışları hakkında kantitatif tahminler yapmak için büyük ölçüde matematiksel modellemeye dayanmaktadır. Bu modeller Mendel’in klasik gen kalıtım ilkelerine, bir popülasyondaki gen frekansını öngören Hardy-Weinberg denge yasasına ve Darwin'in doğal seleksiyon teorisine dayanmaktadır. Son yıllarda, insana ait özellik ve hastalıkların kalıtım derecelerinin (ℎ2) tahmini ile ilgili genom çapında veriler kullanılarak yapılan çalışmalar oldukça yaygındır. İkizlerin kullanıldığı çalışmalardan elde edilen sonuçların büyük bir bölümü, insana ait karmaşık özelliklerin tümünün kalıtsal olduğunu göstermiştir. Kalıtım derecesi, ya toplam genetik varyasyonun (geniş anlamda kalıtım derecesi) ya da eklemeli genetik varyasyonun (dar anlamda kalıtım derecesi) katkısı olarak ölçülür. Özelliklerin ve hastalıkların kalıtım derecesini tahmin etmek için çeşitli yöntemler önerilmiştir. Bir özelliğin kalıtım derecesi, bireyler arasındaki genetik çeşitlilikten kaynaklanan fenotipik varyasyon oranını ifade eder. Karmaşık özelliklerin genetik temeli hakkında önemli bilgiler sağlar ve bir fenotipin daha spesifik istatistiksel ve moleküler genetik analizler için uygun bir hedef olup olmadığını gösterir. Bununla birlikte, kalıtım derecesi bir fenotipin sabit bir özelliği değildir ve genetik arka plan ile çevresel varyasyondaki popülasyona özgü farklılıklara göre değişebilir. Bu çalışmanın amacı, kalıtım derecesini tahmin etmek için yaygın olarak kullanılan üç farklı yöntemi tanıtmaktır.

Anahtar Kelimeler

• Popülasyon,genetik,kalıtım,insan,hastalık

Kaynakça

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