荷特林T2檢定於基因改造產品統計評估之研究

Abstract

根據歐盟（European Union, EU）基改生物（Genetically Modified organism, GMO）的定義為“除了人類以外，其遺傳物質以非天然發生的雜合或重組方式改變之有機生命體”。通常，基改食物為植物產品，例如：玉米、大豆以及棉花。基因改造的目的在於使目標品種在營養成份或是農藝性狀上有較佳的性質，實質相等性（substantial equivalence）是對於這類基因改造作物或是產品之安全性評估的一個相當重要的議題。 在本研究當中，我們會先簡介在基改產品之評估上的實質相等性概念，傳統作物可以作為一新產生的基改作物之對照組，若基改作物與其傳統對照組之間沒有生物上有意義的差距，則我們可以宣稱此基改作物與其傳統對照組之間是實質相等的。考量同一產品內各個營養成份之間的相關性，我們使用荷特林T２方法來檢測基改產品的實質相等性。在本研究中，我們以一資料作為例子說明提出之方法，並進行模擬，比較在不同的相關性以及變數個數下，學生氏ｔ檢定方法與荷特林T２方法對於基改產品安全性評估之表現。

A genetic modified organism (GMO) is defined as “an organism, with the exception of human beings, in which the genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination” (EU Directive 2001/18). Typically, genetically modified foods are plant products such as corn, soybean and cotton. Genetic modification aims to render the resulting plant variety more favorable in nutritional quality or agronomic characteristics. The substantial equivalence is an important concept in the safety assessment of food or/and feed derived from genetically modified crops. In this study, we will first introduce the concept of substantial equivalence for evaluating GM products. An existing traditional crops can served as a basis for comparison for new varieties that has been modified. Substantial equivalence is claimed if no meaningful difference is found between GM product and its non-GM counterpart. Considering the correlation between chemical components within the same product, we applied Hotelling T２ method to evaluate substantial equivalence of GM products. We conducted simulation study in different correlations and different number of variables to compare the performance between the Hotelling T２and T test. A numerical example is used to illustrate the proposed procedure.