POLA1 and cask-related x-linked intellectual disability: Previously, germline variants in POLA1 have been documented in cases of syndromic X-linked reticulate pigmentary disorder (XLRPD; MIM: 312040; Starokadomskyy et al, 2016) and X-linked intellectual disability (XLID; MIM: 301030; Van Esch et al, 2019).