Light micrograph of a section through human tissue showing Carney complex. This refers to a rare genetic disorder characterised by multiple benign tumours (multiple neoplasm) most often affecting the heart, skin and endocrine system. Additionally, this condition shows abnormalities in the skin colouring (pigment) resulting in a spotty appearance to the skin of affected areas. In many cases Carney complex is due to mutations of the PRKAR1A gene. The mutation can occur randomly for no apparent reason (new mutation) or be inherited as an autosomal dominant trait.