Standardized linkage disequilibrium as a function of intermarker distance. Standardized linkage disequilibrium (D') between markers of the X chromosome as a function of the intermarker distance. Large symbols: D' values with nominal p ≤ 0.01 (blue: adjacent markers; red: LD computed at 5-marker intervals). Dots: D' values with p > 0.01. Marker pairs with distance <1 kb have been omitted.