Detection of LOH and X-chromosome inactivation in bone marrow cells and peripheral blood plasma. (A) Representative example showing LOH in bone marrow cells and PB plasma before therapy and disappearance of the LOH when the patient was in remission. (B) Box plots showing positive and negative cases for LOH as detected in 37 BM cell samples from patients with AML. All tested corresponding PB plasma samples (27 samples) showed LOH. (C) Positive and negative cases for LOH detected in 27 samples of BM cells from patients with MDS, while all tested corresponding PB plasma samples (25 samples) showed LOH. (D) Monoclonality and polyclonality were detected by X-chromosome inactivation in BM cell samples from 26 patients with AML or MDS, whereas all tested plasma samples (22 samples) were monoclonal.