Power of some statistical tests for the detection of major genes in quantitative traits: 1. Tests of variance homogeneity

Bu çalışmada, kantitatif karakterlere etkili major genlerin belirlenmesi bakımından dört farklı familya-içi varyans homojenliği testinin güçleri simülasyonla türetilen veriler kullanılarak değerlendiriüniştir. Veriler, dengeli bir üvey-kardeş familya yapısına göre türetilmiştir. Poligenik kalıtım derecesinin 4 düzeyi (0,2, 0,4, 0,6 ve 0,8), iki farklı kalıtım tarzı (kodominant ve dominant), 4 farklı gen frekansı düzeyi (0,2, 0,4, 0,6 ve 0,8) ve 4 farklı gen etkisi düzeyinin (Gp — 0,5,1,0,2,0 ve 3,0) tüm olası kombinasyonuna dayanan toplam 128 farklı major gen açılımı senaryosu değerlendirilmiştir. Sonuçlar gen etkisindeki yükselme ile birlikte tüm testlerin gücünün arttığını göstermiştir. Dominant etkili genlerin belirlenmesinin kodominant etkili genlerden çok daha kolay olduğu gözlemlenmiştir. Gen etkisinin küçük düzeylerinde (0.5 ve 1

Kantitatif karakterlere etkili major genlerin belirlenmesi bakımından kimi istatistiki testlerin güçleri: 1. Varyans homojenliği testleri

In this study the power of four within-femily variance homogeneity tests (Levene, O'Brien, Brown and Forsythe, and Bartlett test) to detect major genes controlling quantitative traits was evaluated using simulated data. The data were simulated according to a balanced half-sib family structure. One hundred and twenty eight scenario of major gene segregation based on all possible combinations from 4 levels of polygenic heritability (0.2,0.4,0.6 and 0.8), 2 modes of inheritance (additive and dominant), 4 levels of gene frequency (0.2,0.4,0.6 and 0.8) and 4 levels of major gene effect in phenotypic standard deviation (

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