Linkage disequilibrium (LD) is something that most people working with standard population genetic analyses have traditionally considered as a nuisance – linked markers do not provide independent information about population history. However, in many other contexts, such as in estimation of effective size of populations, or devising strategies for identifying genes and genomic regions harboring factors responsible for expression of given traits, LD can actually be an asset. However, relatively little is known about extent of LD in wild populations.
In recent paper Menghua has worked out the details and extent of LD in the genome of the Siberian jay population in the margin of the species distribution range. The extent of LD was found to be very high, extending at high levels over considerable distances. Although the extent of LD decayed as function of increasing distance between markers, also long distance LD (e.g. among linkage groups) was common.
Part of the explanation for the high levels of LD is likely to depend on the fact the study population is relatively small and partially inbred. Just as Finns in general.
Li MH & J Merilä (2009) Extensive linkage disequilibrium in a wild bird population. Heredity, in press.