[1] NCI, US Dept HHS, NIH, Bethesda, MD 20892 USA
[2] Natl Inst Gen Med Sci, US Dept HHS, NIH, Bethesda, MD USA
[3] NHGRI, US Dept HHS, NIH, Bethesda, MD 20892 USA
[4] NIA, US Dept HHS, NIH, Bethesda, MD 20892 USA
[5] NIDDK, US Dept HHS, NIH, Bethesda, MD 20892 USA