However, for some other X-linked disorders, such as BFLS induced by PHF6 gene mutation, our case (in pedigree 4) and numerous previous reports all uncovered that the XCI pattern of blood cell has poor prognostic value for clinical consequences (Crawford et al., 2006; Berland et al., 2011; Zhang et al., 2019). This evidence concerns the gene PHF6 and Borjeson-Forssman-Lehmann syndrome.