Six members of a family had various manifestations of the syndrome, anhidrotic ectodermal dysplasia; included in this family were identical twin boys with all the stigmas of this syndrome. In addition to the usual cutaneous changes associated with the syndrome, myriads of sebaceous gland papules were seen on the malar areas, nasolabial folds, and foreheads of the identical twins. The genetics of inheritance of this syndrome in this family conformed to that commonly accepted (X-linked recessive).
Katz SI, Penneys NS. Sebaceous Gland Papules in Anhidrotic Ectodermal Dysplasia. Arch Dermatol. 1971;103(5):507-509. doi:10.1001/archderm.1971.04000170041010