{'fraction_non_alphanumeric': 0.024798927613941018, 'fraction_numerical': 0.012734584450402145, 'mean_word_length': 6.177884615384615, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Characterization of human bone marrow‐derived closed circular DNA clones

Because of interest in mechanisms of recombination involved in chromosomal deletions in neoplastic disease, and their relation to possible rearrangements in normal tissues, we are studying circular DNA molecules from human tissue with a long‐term goal of investigating them as possible by‐products of physiologically relevant intrachromosomal recombination events. Covalently closed circular (ccc) DNA from human bone marrow was cloned in bacteriophage vectors, and fourteen clones chosen randomly from the cccDNA‐derived library were characterized. Five clones originated from chromosome‐specific centromeric α‐satellite DNA; two clones carried highly repetitive sequences probably derived from interspersed repetitive elements; six clones were derived from single‐copy chromosome‐specific sequences which detected homologous rodent sequences; and one clone (EPM10) was derived from a small chromosome 11‐specific sequence family which localized to chromosome regions 11cen and 11q14. Oligonucleotide primers derived from the cccDNA clones were used in polymerase chain reaction studies to show that (1) the EPM10 clone carried the circular junction, (2) several of the single‐copy products could be detected in three different bone marrow cccDNA preparations, and (3) the Alu‐PCR profile for bone marrow cccDNA showed distinct bands which were similar in four bone marrow cccDNA preparations. © 1993 Wiley‐Liss, Inc.