Chromosome 2 of Plasmodium falciparum was sequenced; this sequence contains 947,103 base pairs and encodes 210 predicted genes. In comparison with the Saccharomyces cerevisiae genome, chromosome 2 has a lower gene density, introns are more frequent, and proteins are markedly enriched in nonglobular domains. A family of surface proteins, rifins, that may play a role in antigenic variation was identified. The complete sequencing of chromosome 2 has shown that sequencing of the A+T-rich P. falciparum genome is technically feasible.

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Background Two large-scale prostate cancer screening trials with prostate-specific antigen (PSA) have given conflicting results in terms of the efficacy of such screening. One of those trials, the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, previously reported outcomes through 13 years of follow-up. Here we present updated findings from PLCO. Methods PLCO randomized subjects from 1993–2001 to an intervention or control arm. Intervention arm men received annual PSA tests for six years and digital rectal exam for four years. We used linkage with the National Death Index (NDI) to extend mortality follow-up to a maximum of 19 years from randomization. Results 38,340 and 38,343 men were randomized to the intervention and control arms, respectively. Median (25th/75th) follow-up time was 14.8 years (12.7/16.5) in the intervention and 14.7 years (12.6/16.4) in the control arm. 255 (intervention arm) versus 244 (control arm) deaths from prostate cancer were observed, for a rate-ratio (RR) of 1.04 (95% CI: 0.87–1.24). The RR for all-cause mortality was 0.977 (95% CI: 0.950,1.004). An estimated 86% of control versus 99% of intervention arm men received any PSA testing during the trial, with estimated yearly screening phase PSA testing rates of 46% (control) versus 84% (intervention). Conclusion Extended follow-up of PLCO over a median of 15 years continues to indicate no reduction in prostate cancer mortality for the intervention compared to control arms. Due to the high rate of control arm PSA testing, this finding can be viewed as showing no benefit of organized over opportunistic screening.