mtDNA analysis does not detect Asian lineages in Cameroon

In a recent high-resolution study of Y-chromosome variation it has been observed that the haplotype 117 (belonging to the haplogroup IX) occurs at a frequency ranging from 0% to 95% in northern Cameroon. This finding is of particular interest since the 117 haplotype seems to have been involved in a back migration from Asia to Africa. As a logical development of this study, we have analyzed mitochondrial variation in the same populations analyzed for Y chromosomes (Bakaka, Bamileke, Daba, Ewondo, Fali, Fulbe, Ouldeme and Tali) and in four additional populations (Bassa, Mandara, Tupuri and Podokwo). We analyzed the hypervariable region-1 by a standard sequencing method and 4 nucleotide positions of the mtDNA coding region (10400, 12308 and 12705, 10873) using the Snapshot method in a total of 439 individuals. We observed five different haplogroups, three of which ate sub-Saharan (L1, L2, L3), one northern African (U6) and one European (U5). The presence of the northern African haplogroup (among Podokwo and Uldeme) could be due to recent gene flow from north-eastern Africa. The U5 haplogroup was found only in one Fulbe individual. The lack of Asian haplogroups in Cameroon suggests that the migratory flow which spread the 117 haplotype was conducted predominantly by males and that the female contribution, ir present, was not as large to escape extinction by genetic drift.