Examples of types of defects detected by SNP-A. Various types of chromosomal lesions detectable by SNP-A are presented, including microdeletions and microgains, large segmental or numeric gains, losses, and segmental acquired UPD. For demonstration purposes, the somatic nature of an exemplary microdeletion detected in bone marrow is demonstrated by comparison with sorted, nonclonal CD3 cells from the same patient. The karyogram of CD3 cells shows 2 normal chromosomes 7. Below, a similar demonstration is provided for an exemplary UPD with a disparity in the density of heterozygosity calls between clonal bone marrow sample and nonclonal sorted CD3 T cells.