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Chen et al. (Reports, 28 October 2016, p. 468) proposed that an interaction between Xist RNA and Lamin B receptor (LBR) is necessary and sufficient for Xist spreading during X-chromosome inactivation. We reanalyzed their data and found that reported genotypes of mutants are not supported by the sequencing data. These inconsistencies preclude assessment of the role of LBR in Xist spreading.