This book covers the statistical models and methods that are used to understand human genetics. Firstly, the ABO blood group system of man has been described by discussing the multiple alleles; genotypes, Gene Frequencies and phenotypes of blood groups.Secondly,the three genetic parameters in this theory of Genetics namely, Heritability coefficient, Repeatability coefficient of Genetic correlation coefficients have been explained and the methods for estimating there genetic parameters have been developed in the present research work. Thirdly, a test for homogeneity in genetics by using Meta-Analysis has been proposed in the study, Here for k studies, a weighted average of the logarithms of odds ratios has been suggested for testing the homogeneity.Fourthly, the Meta-Analytic Technique for combining diagnostic tests has been developed in the present research study. This technique has been discussed by using the concept of Sensitivity and Specificity. Finally an Iterative procedurefor estimating the Gene Frequencies has been proposed. The maximum likelihood estimation methods have been used by taking Bernstein estimates as initial estimates for the iterative procedure.