1. The genetical foundation. - 1. Continuous variation. - 2. The genic basis. - 3. Assaying the chromosomes. - 4. Locating the genes. - 2. The biometrical approach. - 5. The manifestation of polygenic systems. - 6. Genetic analysis and somatic analysis. - 7. Biometrical genetics. - 3. Additive and dominance effects. - 8. Components of means. - 9. Testing the model. - 10. Scales. - 11. Components of variation: F2 and back-crosses. - 12. Generations derived from F2. - 13. The balance sheet of genetic variability. - 14. Partitioning the variation. - 4. Diallels. - 15. The principles of diallel analysis. - 16. An example of a simple diallel. - 17. Undefined diallels. - 18. An example of an undefined diallel. - 5. Genic interaction and linkage. - 19. Non-allelic interaction. - 20. Interaction as displayed by means. - 21. Variances and covariances. - 22. Correlated gene distributions: linkage. - 23. Diallels. - 6. Interaction of genotype and environment. - 24. Genotype x environment interaction. - 25. Two genotypes and two environments. - 26. A more complex case. - 27. The relation of g to e. - 28. Crosses between inbred lines. - 29. Variance of F2. - 7. Randomly breeding populations. - 30. The components of variation. - 31. Human populations. - 32. The use of twins. - 33. Experimental analysis. - 34. Complicating factors. - 35. Heritability. - 8. Genes and effective factors. - 36. Estimating the number of segregating genes. - 37. Consequences of linkage: effective factors. - 38. Other sources of estimates. - 9. Conclusion. - 39. Designing the experiments. - 40. Concepts and uses. - Glossary of symbols and abbreviations. - References. Language: English