Theoretical recombination processes incorporating interference effects
The calculation of recombination rates among multiple markers on chromosomes is usually based on independence assumptions for all segments involved. These assumptions are unrealistic since the occurrence of crossover genetic exchange between two adjacent markers generally implies a reduced change of a crossover event over the segment extending to the exact marker (positive interference). This paper contains both review material and new results with emphasis on two topics: (i) classifications and characterizations of multimarker recombination distributions; (ii) analysis of regular and higher order crossover interference forms. In Section 2 we survey briefly some background material covering data and mechanisms of crossover (chiasma) formation processes. Section 3 describes various concepts and measures of interference between chromosomal regions. In Section 4 a number of issues are raised concerning the standard construction of genetic map functions (linkage relationships) for sets of genetic markers. Sections 5-7 describe several global multimarker crossover processes. The nature and extent of interference (regular and higher order) for these processes are characterized in Sections 8 and 9. The problematical nature of several families of genetic map functions in current practice is discussed in Section 10. The degree of validity of LOD score methodology relative to assignments of loci to physical band locations is examined briefly in Section 11.
higher order crossover interference forms
scientific article; zbMATH DE number 703283