Diallel cross
A diallel cross is a mating scheme used by plant and animal breeders, as well as geneticists, to investigate the genetic underpinnings of quantitative traits.[1][2]
In a full diallel, all parents are crossed to make hybrids in all possible combinations. Variations include half diallels with and without parents, omitting reciprocal crosses.[3] Full diallels require twice as many crosses and entries in experiments, but allow for testing for maternal and paternal effects.[4] If such "reciprocal" effects are assumed to be negligible, then a half diallel without reciprocals can be effective.
Common analysis methods utilize general linear models to identify heterotic groups,[5] estimate general or specific combining ability,[6][7] interactions with testing environments and years, or estimates of additive, dominant, and epistatic genetic effects[8][9] and genetic correlations.[10]
Mating designs
There are four main types of diallel mating design:
- Full diallel with parents and reciprocal F1 crosses
- Full diallel as above, but excluding parents
- Half diallel with parents, but without reciprocal crosses
- Half diallel without parents or reciprocal crosses
References
- Hallauer, A. R. and J. B. Miranda Filho. 1988 Quantitative genetics in maize breeding. 2nd ed. Iowa State University Press, Ames, IO.
- Crusio WE, Kerbusch JM, van Abeelen JHF (January 1984). "The replicated diallel cross: a generalized method of analysis". Behavior Genetics. 14 (1): 81–104. doi:10.1007/BF01066070. PMID 6712552.CS1 maint: multiple names: authors list (link)
- Jones, R. M. (1965). "Analysis of variance of the half diallel table". Heredity. 20 (1): 117–121. doi:10.1038/hdy.1965.12.
- Crusio WE (December 1987). "A note on the analysis of reciprocal effects in diallel crosses". Journal of Genetics. 66 (3): 177–185. doi:10.1007/BF02927711. Retrieved 2009-08-14.
- Griffing, B. 1956. Concept of general and specific combining ability in relation to diallel crossing systems. Australian Journal of Biological Sciences 9: 463-493
- Gardner, C. O. and S. A. Eberhart. 1966. Analysis and interpretation of the variety cross diallel and related populations. Biometrics 22: 439-452
- Sprague G. F., and L. A. Tatum. 1942. General vs. specific combining ability in single crosses of corn. J. Am. Soc. Agron. 34: 923-932
- Hayman, B. I. 1954. The analysis of variance of diallel tables. Biometrics 10: 235-244
- Hayman BI (November 1954). "The theory and analysis of diallel crosses". Genetics. 39 (6): 789–809. PMC 1209689. PMID 17247520. Retrieved 2010-03-02.
- Crusio WE (January 1993). "Bi- and multivariate analyses of diallel crosses: a tool for the genetic dissection of neurobehavioral phenotypes". Behavior Genetics. 23 (1): 59–67. doi:10.1007/BF01067554. PMID 8476392.