In IP patients positive for neutralizing auto-Abs against type I IFNs, autoreactivity was clearly strongest against various type I IFNs, including IFN-α1, IFN-α2, IFN-α4, IFN-α6, IFN-α7, IFN-α8, and IFN-α14 (Fig. 1 D, Fig. S1 E, and Table S2). This evidence concerns the gene IFNA4 and incontinentia pigmenti.