Incontinentia pigmenti (IP) is a disorder that affects the skin, hair, teeth, nails, eyes, and central nervous system; it occurs primarily in females and on occasion in males. Characteristic skin lesions evolve through four stages: I. Blistering (birth to age ~4 months). II. Wart-like rash (for several months). III. Swirling macular hyperpigmentation (age ~6 months into adulthood). IV. Linear hypopigmentation. Alopecia, hypodontia, abnormal tooth shape, and dystrophic nails are observed. Neovascularization of the retina, present in some individuals, predisposes to retinal detachment. Neurologic findings including seizures, intellectual disability, and developmental delays are occasionally seen.

Scalp-ear-nipple syndrome is characterized by aplasia cutis congenita of the scalp, breast anomalies that range from hypothelia or athelia to amastia, and minor anomalies of the external ears. Less frequent clinical characteristics include nail dystrophy, dental anomalies, cutaneous syndactyly of the digits, and renal malformations. Penetrance appears to be high, although there is substantial variable expressivity within families (Marneros et al., 2013).

Estrogen resistance (ESTRR) is characterized by absence of puberty with elevated estradiol and gonadotropic hormones, as well as markedly delayed bone maturation. Female patients show absent breast development, small uterus, and enlarged multicystic ovaries; male patients may show small testes (Bernard et al., 2017). Some patients exhibit continued growth into adulthood (Smith et al., 1994).

The 10q22.3-q23.2 region is characterized by a complex set of low-copy repeats (LCRs), which can give rise to various genomic changes mediated by nonallelic homologous recombination (NAHR). Recurrent deletions of chromosome 10q22.3-q23.2, including the BMPR1A gene (601299) have been associated with dysmorphic facies, developmental delay, and multiple congenital anomalies. Some patients with deletions that extend distally to include the PTEN gene (601728) have a more severe phenotype with infantile/juvenile polyposis, macrocephaly, dysmorphic facial features, and developmental delay (summary by van Bon et al., 2011).

Any Meier-Gorlin syndrome in which the cause of the disease is a mutation in the CDC45 gene.