Abstract
A genetic map function M(d) = RF provides a mapping from the additive genetic distance d to the non-additive recombination fraction RF between a given pair of loci, where the recombination fraction is the proportion of gametes that are recombinant between the two loci. Genetic map functions are needed because in most experiments all we can directly observe are the recombination events. However, since a recombination event is only observed if there are an odd number of crossovers between the two loci, recombination fractions are not additive. One of the most widely used map functions is Haldane’s map function, which is derived under the assumptions of no chiasma and no chromatid interference, and has been in widespread use since 1919. However, Casares recently proposed a ‘corrected’ Haldane’s map function – we show here that this ‘corrected’ map function is not correct due to faulty assumptions and mistakes in its derivation.
This is a preview of subscription content, log in via an institution to check access.
References
Bailey NTJ (1961) Introduction to the mathematical theory of genetic linkage. Clarendon Press, Oxford
Casares P (2007) A corrected Haldane’s map function to calculate genetic distances from recombination data. Genetica 129:333–338
Emerson RA, Rhoades MM (1933) Relation of chromatid crossing over to the upper limit of recombination percentages. Am Nat 67:374–377
Haldane JBS (1919) The combination of linkage values and the calculation of distances between the loci of linked factors. J Genet 8:299–309
Lange K (2002) Mathematical and statistical methods for genetic analysis, 2nd edn. Springer, New York
Mather K (1936) The determination of position in crossing-over I. Drosophila melanogaster. J Genet 33:207–235
Mather K (1938) Crossing-over. Biol Rev Camb Philos Soc 13:252–292
McPeek MS (1996) An introduction to recombination and linkage analysis. In: Speed TP, Waterman MS (eds) Genetic mapping and DNA sequencing: IMA volumes in mathematics and its applications. Springer-Verlag, New York, pp 1–14
Speed TP (1996) What is a genetic map function? In: Speed TP, Waterman MS (eds) Genetic mapping and DNA sequencing: IMA volumes in mathematics and its applications. Springer-Verlag, New York, pp 65–88
Speed TP (2005) Genetic map functions. In: Encyclopedia of Biostatistics. Wiley, New York
Weeks DE (1994) Invalidity of the Rao map function for three loci. Hum Hered 44:178–180
Weeks DE, Lathrop GM, Ott J (1993) Multipoint mapping under genetic interference. Hum Hered 43:86–97
Weeks DE, Ott J, Lathrop GM (1994) Detection of genetic interference: simulation studies and mouse data. Genetics 136:1217–1226
Acknowledgments
We would like to acknowledge the support of the University of Pittsburgh and NIH grant R01GM076667.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Weeks, D.E., Tang, X. & Kwon, A.M. Casares’ map function: no need for a ‘corrected’ Haldane’s map function. Genetica 135, 305–307 (2009). https://doi.org/10.1007/s10709-008-9287-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10709-008-9287-1