{'fraction_non_alphanumeric': 0.029511918274687854, 'fraction_numerical': 0.029511918274687854, 'mean_word_length': 4.617834394904459, '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}}
Identification of RB and p53 mutations in mouse lymphoma cell lines

We analyzed the genomic structure and mRNA of the RB and p53 genes in four mouse lymphoid leukemia cell lines (DL‐1, DL‐5, DL‐8, and DL‐12). Although no gross structural alteration of the RB gene was observed in any cell line, abnormalities of RB mRNA were detected in at least two cell lines. RB mRNA expression was greatly reduced in DL‐12. In addition, cloning and sequencing analysis of the RB cDNA revealed that the RB mRNA in DL‐8 had a 276‐nucleotide deletion presumably consisting of exons 10, 11, and 12, suggesting that altered splicing resulted in the loss of these exons. Analysis of the p53 gene indicated that DL‐5 had a deletion in both alleles and expressed a smaller mRNA. These results suggest that mutations of the RB or p53 genes, or both, are associated with lymphoid leukemogenesis in mice.