Germline sequence variants contributing to cancer susceptibility in South African breast cancer patients of African ancestry.

Since the discovery of the breast cancer susceptibility genes, BRCA1 and BRCA2, various other genes conferring an increased risk for breast cancer have been identified. Studies to evaluate sequence variants in cancer predisposition genes among women of African ancestry are limited and mostly focused on BRCA1 and BRCA2. To characterize germline sequence variants in cancer susceptibility genes, we analysed a cohort of 165 South African women of self-identified African ancestry diagnosed with breast cancer, who were unselected for family history of cancer. With the exception of four cases, all others were previously investigated for BRCA1 and BRCA2 deleterious variants, and were negative for pathogenic variants. We utilized the Illumina TruSight cancer panel for targeted sequencing of 94 cancer susceptibility genes. A total of 3.6% of patients carried a pathogenic/likely pathogenic variant in a known breast cancer susceptibility gene: 1.2% in BRCA1, 0.6% in each of BRCA2, ATM, CHEK2 and PALB, none of whom had any family history of breast cancer. The mean age of patients who carried deleterious variant in BRCA1/BRCA2 was 39 years and 8 months compared to 47 years and 3 months among women who carried a deleterious variant in other breast cancer susceptibility genes.

Tick-borne haemoparasites in African buffalo (Syncerus caffer) from two wildlife areas in Northern Botswana.

BACKGROUND: The African buffalo (Syncerus caffer) is a host for many pathogens known to cause economically important diseases and is often considered an important reservoir for livestock diseases. Theileriosis, heartwater, babesiosis and anaplasmosis are considered the most important tick-borne diseases of livestock in sub-Saharan Africa, resulting in extensive economic losses to livestock farmers in endemic areas. Information on the distribution of tick-borne diseases and ticks is scarce in Northern Botswana. Nevertheless, this data is necessary for targeting surveillance and control measures in livestock production at national level. METHODS: In order to address this gap, we analyzed 120 blood samples from buffalo herds for the presence of common tick-borne haemoparasites causing disease in livestock, collected in two of the main wildlife areas of Northern Botswana: the Chobe National Park (CNP, n=64) and the Okavango Delta (OD, n=56). RESULTS: Analysis of the reverse line blot (RLB) hybridization assay results revealed the presence of Theileria, Babesia, Anaplasma and Ehrlichia species, either as single or mixed infections. Among the Theileria spp. present, T. parva (60%) and T. mutans (37%) were the most prevalent. Other species of interest were Anaplasma marginale subsp. centrale (30%), A. marginale (20%), Babesia occultans (23%) and Ehrlichia ruminantium (6%). The indirect fluorescent antibody test (IFAT) indicated 74% of samples to be positive for the presence of T. parva antibodies. Quantitative real-time PCR (qPCR) detected the highest level of animals infected with T. parva (81% of the samples). The level of agreement between the tests for detection of T. parva positive animals was higher between qPCR and IFAT (kappa=0.56), than between qPCR and RLB (kappa=0.26) or the latter and IFAT (kappa=0.15). CONCLUSIONS: This is the first report of tick-borne haemoparasites in African buffalo from northern Botswana, where animals from the CNP showed higher levels of infection than those from OD. Considering the absence of fences separating wildlife and livestock in the CNP and the higher levels of some parasite species in buffalo from that area, surveillance of tick-borne diseases in livestock at the interface in the CNP should be prioritized.