A new sex-specific genetic map of the human pseudoautosomal regions (PAR1 and PAR2)

Abstract

Objectives: Accurate sex-specific genetic maps are essential for gene mapping projects when using multipoint methods, especially for the pseudoautosomal regions (PARs). This paper describes a new sex-specific genetic map for the human PARs. Methods: We used multipoint linkage analysis, three-generation pedigrees and to date, the largest set of genetic markers to estimate recombination events in the PARs. The new map combines genotype data from 28 CEPH pedigrees and 29 genetic markers. All genetic markers have been physically mapped, thus providing the opportunity to compare genetic to physical distance through all the intervals. Results: Recombination activity in PAR1 is on average 7-fold higher in male than in female meiosis, resulting in a much larger genetic map for males. This new map shows how genetically different in size is the X chromosome between males and females. Conclusions: Genetic distances vary extremely between males and females in the PARs. These differences should be considered in genetic studies using accurate sex-specific maps instead of sex-averaged maps. The new map provides a significantly different length compared to some previously published maps, since a much higher number of genetic markers is used. Therefore, we conclude that our map is the most accurate resource for obtaining genetic map information for the PARs. © 2009 S. Karger AG, Basel.