 Complete the following phrase:  In 1997, DNA analysis was carried out on a tooth of Cheddar Man, human remains dated to c. 7150 BC found in Goughs Cave at Cheddar Gorge. His mitochondrial DNA mtDNA belonged to Haplogroup U5. Within modern European populations, U5 is now concentrated in North-East Europe, among members of the Sami people, Finns, and Estonians. This distribution and the age of the haplogroup indicate that individuals belonging to U5 were among the first people to resettle Northern Europe, following the retreat of ice sheets from the Last Glacial Maximum, about 10,000 years ago. It has also been found in other Mesolithic remains in Germany, Lithuania, Poland, Portugal, Russia, Sweden, France and Spain. Members of U5 may have been one of the most common haplogroups in Europe, before the 