Autosomal dominant, PTEN gene (10q23). See OMIM.

Clinically –

• Macrocephaly
• Skin lesions – esp hamartomatous. Eg trichilemmomas (smooth, skin coloured, warty or dome like lesions, esp face), acral keratoses (ie on hands), papillomatous papules)
• Increased risk for the development of breast, thyroid, and endometrial carcinoma

In some cases intestinal polyps, papilloedema, immunodeficiency.