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Ayieko, C.

Publications and source records attributed to Ayieko, C..

2 recordsLinked to original sources

The Origin and Migration of the Ameru Community in Kenya based on mtDNA analysis.

Human diversity did not only remain restricted to their socio-cultural and linguistic domains but also have penetrated deep inside their genetic root. Africa harbors more genetic diversity than any other part of the world. Diversification of the African lineages were complex, involving long-distance gene flow. Data from Africansis needed to better understand the origin and evolution of modern humans, the genetic basis local adaptation, and the evolution of complex traits and related diseases. This analysis formed the basis for this study of determining the origin and migration of the Ameru community in Kenya. Blood samples was collected from 132 male adults of 65 year and above. DNA was extracted and analyzed for the Hyper variable region 1and 2. The sequences were sequenced using Sanger sequence alignment and analyzed using Geneious. Phylogenetic analysis was done using Mega-X while haplotype analysis was done using DNASP software. L1 haplogroup (2.9%) was found among Igembe (7%), Tharaka (6%), and Chuka (7%) and is common in West, Central, and parts of East Africa. L2 haplogroup (6.7%) was present in all subgroups except Imenti and Tigania, indicating West and Central African maternal ancestry. L1 and L2 haplotypes indicate that most Ameru subgroups share partial maternal ancestry from West and Central Africa, while Imenti and Tigania have different maternal lineages. L0-L4 haplogroups indicate predominant East, Central, and West African maternal origins, with subgroups showing variation in haplotype frequencies (e.g., L1 and L2 in Igembe, Tharaka, Chuka; L3 in Tharaka, Mwimbi, Chuka; L4 across all subgroups). Subgroup differences suggest that certain communities, particularly Imenti, have distinct maternal lineages, with less contribution from L1, L2, and L3 but potential links to Afro-Asiatic groups via L4 (found in the Middle East). Non-African haplogroups (N and R) point to historical interactions or shared ancestry with populations in Eurasia and the Horn of Africa, primarily in Tigania and Imenti. Overally, the Ameru maternal gene pool is heterogeneous, shaped by multiple migration routes and interactions across East Africa and beyond, with subgroup-specific maternal histories.

evolutionary biology↗

The Impact of Malaria-Induced Neutrophil Subset Shift and a Link to Burkitt Lymphoma

Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that remains a leading cause of childhood cancer mortality in sub-Saharan Africa. Although the epidemiological link between Plasmodium falciparum (Pf) malaria and BL has been established, our understanding of the underlying immunological mechanisms conducive to tumorigenesis is incomplete. To address a noted gap in our knowledge of the immune landscape, we profiled neutrophil subsets from children with different exposure histories to Pf-malaria and children diagnosed with BL from Western Kenya, along with healthy malaria-naive Kenyan adults. Using multiparameter flow cytometry, we characterized neutrophils by expression of CD15, CD16, CD10, CD11b, CD182, CD184, and CD62L and found that malaria-exposed children exhibited increased frequencies of aged neutrophil subsets, accompanied by a reduction in the mature subset frequencies compared to malaria-naive children. Malaria-exposed children also had neutrophil profiles that closely resembled those seen in the adults. Notably, a positive correlation (rs = 0.7; p < 0.0001) was observed in immature neutrophils between malaria-exposed healthy and BL children, indicating a similar expansion pattern of this subset in both groups. This finding suggests a malaria-driven expansion of the immature subset, potentially promoting a permissive environment for BL. Our data suggests that the observed shift in neutrophil profiles could contribute to the malaria-induced immunopathology associated with BL Visual abstractCreated in BioRender. Forconi, C. (2025) https://BioRender.com/oz60qvq O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/681992v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@1640dc4org.highwire.dtl.DTLVardef@1c3e794org.highwire.dtl.DTLVardef@98bf12org.highwire.dtl.DTLVardef@2851b8_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗