Xeroderma pigmentosum (XP) | XPA, ERCC3 (XPB), XPC, ERCC2 (XPD), DDB2 (XPE), ERCC4 (XPF), ERCC5 (XPG), ERCC1, and POLH (XP-V) | Autosomal recessive | Sun sensitivity, melanoma and nonmelanoma skin and ocular cancers, neurologic abnormalities | Cutaneous: melanoma and nonmelanoma skin cancer at UV-exposed areas of the body, severe sunburn, persistent erythema, facial freckling < age 2, xerosis, poikiloderma Noncutaneous: Ocular: photophobia, keratitis, increased eye lid pigmentation, atrophy of the eye lid skin Nervous system: progressive sensorineural hearing loss, cognitive impairment, abnormal deep tendon stretch reflexes, acquired microcephaly | Clinical testing available for XPA and XPC Limited availability for other XP-related genetic testing outside of research testing. |
Nevoid basal cell carcinoma syndrome (BCNS; see Chap. 113) | PTCH1 PTCH2a SUFUa | Autosomal dominant, approximately 40% of cases are de novo4 | Basal cell carcinoma, jaw keratocysts, skeletal abnormalities, characteristic facial features, ectopic calcification, cardiac and ovarian fibromas, medulloblastoma | One major criteria and molecular confirmation, two major criteria, or one major and two minor criteria (adapted from): Major criteria: Basal cell carcinoma (BCC) < age 20 or excessive number of BCCs; odontogenic keratocysts of the jaw (histologically proven) < age 20; palmar or plantar pits; lamellar calcification of the falx cerebri; medulloblastoma; first-degree relative with BCNS. ... |