The pattern of linkage disequilibriurn (LD) is affected by a number of factors, including population dernography. High LD is seen in populations with a relatively limited and constant size, presurnably due to genetic drift. We have examined the extent of LD arnong over 300 genome-wide pattern microsatellite loci in 29 populations from around the world. The pattern of LD vari ed between populations, with larger extent of LO in populations with limited size relative to larger populations. In addition, the LD between 88 less spaced microsatellite ffiarkers from 10 different genornic regions were examined in the Sami compared to the general Swedish population. For the se ffiarkers increased LD extending up to 5 Mb was detected in the Sami. The arnount of LD also differed between the chrornosornal regions. The arnount of LD in the Sami makes this population suited for mapping ofcornplex genetic traits