In human genetics, Haplogroup R1b is the most frequently occurring Y-chromosome haplogroup in Western Europe. More specifically, R1b's frequency is highest in the populations of Atlantic Europe and, due to European emigration, in North America, South America, and Australia. In Ireland and the Basque Country its frequency exceeds 90% and approaches 100% in Western Ireland. The incidence of R1b is 70% or more in parts of northern and western England, northern Spain, northern Portugal, western France, Wales, Scotland. R1b's incidence declines gradually with distance from these areas but it is still common across the central areas of Europe. R1b is the most frequent haplogroup in Germany, and is common in Czech Republic, southern Scandinavia and in Italy.