ON THE PLANNING OF SAMPLES FOR LINKAGE AN ALYSIS - A SAMPLE-SIZE

There is a proposed method for evaluation of the minimal sample size n eeded for the predefined quality of the linkage decision. It is applie d to samples of arbitrary structured pedigrees ascertained via proband in accordance with different ascertainment schemes. The quality of th e linkage decision is determined by the I and II type errors of the li kelihood ratio constructed with a simple alternative hypothesis about the recombination fraction value. Comparison of these minimal sample s izes for different ascertainment schemes leads to a possibility to cho ose the best of them when the model of genetic control of two traits i s given. A possibility to evaluate each of these ascertainments by a c ost of the sample collection and to point out the cheapest is consider ed.