Supporters of the Solutrean hypothesis had pointed to the presence of haplogroup X2, the global distribution of which is strongest in Anatolia and the northeast of America, a pattern they argue is consistent with their position. Michael Brown in a 1998 article identified this as evidence of a possible Caucasian founder population of early Americans spreading from the northeast coast. However, a 2008 article in the "American Journal of Human Genetics" by researchers in Brazil took up the argument against the Solutrean hypothesis. "Our results strongly support the hypothesis that haplogroup X, together with the other four main mtDNA haplogroups, was part of the gene pool of a single Native American founding population; therefore they do not support models that propose haplogroup-independent migrations, such as the migration from Europe posed by the Solutrean hypothesis."