ANOTHER PROCEDURE FOR THE PRELIMINARY ORDERING OF LOCI BASED ON 2 POINT LOD SCORES

Because of the difficulty of performing full likelihood analysis over multiple loci and the large numbers of possible orders, a number of me thods have been proposed for quickly evaluating orders and, to a lesse r extent, for generating good orders. A new method is proposed which u ses a function which is moderately laborious to compute, the sum of lo d scores between all pairs of loci. This function can be smoothly mini mized by initially allowing the loci to be placed anywhere in space, a nd only subsequently constraining them to lie along a one-dimensional map. Application of this approach to sample data suggests that it has promise and might usefully be combined with other methods when loci ne ed to be ordered.