Fig. 1From: Single nucleotide polymorphisms in the bovine MHC region of Japanese Black cattle are associated with bovine leukemia virus proviral loadProviral load estimated from SNP typing of DNA samples from 444 BLV-infected Japanese Black cattle (a) and 858 samples from Japanese Black cattle located in 22 prefectures of Japan (b) [17]. The proviral load in the 444 test samples was representative of the proviral load in Japanese Black cattle nationwide (p value, p = 0.4244; F test). Blood (collected in EDTA-2Na) was obtained from 444 Japanese black cows (aged >4 years), and genomic DNA was extracted from whole blood using the QIAsymphony kit (QIAGEN K.K., Tokyo, Japan). The BLV-CoCoMo-qPCR-2 method (RIKEN genesis, Kanagawa, Japan) was used to measure the BLV proviral load in 676 cattle at a single time-point; of these, 444 were positive for BLV and entered into the association study. Briefly, the BLV long terminal repeat region was amplified using a degenerate primer pair (CoCoMo-FRW and CoCoMo-REV) and an FAM-BLV probe. The BoLA-DRA gene (internal control) was amplified using the primer pair DRA-F and DRA-R and the FAM-DRA probe [31]Back to article page