Genome-wide association study identifies novel breast cancer susceptibility loci

Breast cancer exhibits familial aggregation, consistent with variation in genetic susceptibility to the disease. Known susceptibility genes account for less than 25% of the familial risk of breast cancer, and the residual genetic variance is likely to be due to variants conferring more moderate risks. To identify further susceptibility alleles, we conducted a two-stage genome-wide association study in 4,398 breast cancer cases and 4,316 controls, followed by a third stage in which 30 single nucleotide polymorphisms (SNPs) were tested for confirmation in 21,860 cases and 22,578 controls from 22 studies. We used 227,876 SNPs that were estimated to correlate with 77% of known common SNPs in Europeans at r2 > 0.5. SNPs in five novel independent loci exhibited strong and consistent evidence of association with breast cancer (P < 10(-7)). Four of these contain plausible causative genes (FGFR2, TNRC9, MAP3K1 and LSP1). At the second stage, 1,792 SNPs were significant at the P < 0.05 level compared with an estimated 1,343 that would be expected by chance, indicating that many additional common susceptibility alleles may be identifiable by this approach.     

不同碳氮源对一株产油小球藻油脂积累的影响

以蛋白核小球藻(Chlorella pyrenoidosa)为研究对象,考察了不同碳源及氮源对小球藻生物量和油脂产率的影响,确定了最佳碳源和氮源的添加量.结果表明,蛋白核小球藻最优碳源是葡萄糖,最优氮源是尿素;当葡萄糖浓度为30mg/L、尿素浓度为1.5mg/L时,小球藻生物量和油脂产率达到8783.9mg/L和126.3mg/L/d,比优化前分别提高了37.9%和125%.这为今后培养小球藻,提高其生物量和油脂产率奠定了一定的理论基础.