 A 2003 study by Weale et al., of the DNA of over 8,000 males worldwide, found that five out of 1,247 Nigerian males belonged to DE*.The DE* found possessed by these five Nigerians, according to the study's authors, was "the least derived of all YAP chromosomes according to currently known binary markers" – to such an extent that it suggested that DE had originated in West Africa and expanded from there.However, Weale et al., cautioned that such inferences may well be incorrect.