A recurrent pattern of somatic copy number abnormalities and UPD in FA BM cells. All acquired copy number and UPD regions found in the BM cells of 57 individuals with FA are shown. Green lines represent deletions; red lines, gains; and blue lines, regions of UPD (somatic copy-neutral loss of heterozygosity). Constitutional copy-neutral homozygosity regions are not shown. The RUNX1 gene location at 21q22 is shown.