CALCULATION OF LIKELIHOOD RATIO Y-X IN DIAGNOSIS OF PATERNITY USING COMPUTER METHODS

A new computational method using a Monte Carlo technique is described for the calculation of plausibility of paternity in blood group systems. Gene frequencies of a blood group system are simulated by the range of 7 digit random numbers. By using a Monte Carlo method, 4 random numbers are generated and converted into paternal and maternal genotypes. The genotype of the child is determined according to the law of inheritance and genotypes of the father, mother and child are converted into phenotypes. Repeating this process more than 100,000 times, the phenotypic frequencies of child-mother-father combinations (trio) and the likelihood ratio of paternity in any blood group system are calculated for all phenotypic combinations of the trios. This method is easier than methods reported previously, and is sufficiently accurate.