• history of neurofibromatosis
• mosaicism
• neurofibromatosis type 1
• segmental neurofibromatosis

Neurofibromatosis type 1 (NF1) and type 2 both occur in mosaic (segmental) forms.¹ When NF1 (and other autosomal dominant skin disorders)^1,2 occurs in a linear, patchy, quadrant, or otherwise localised form, two different types of mosaicism can be distinguished.² Type 1 segmental involvement reflects heterozygosity for a postzygotic mutation occurring in an otherwise healthy embryo. The segmental lesions are limited to the affected area and show the same degree of severity as that found in the corresponding non-mosaic trait (for example, mosaic/segmental NF1). Type 2 segmental involvement occurs in a heterozygous embryo and reflects loss of heterozygosity that occurred at an early developmental stage. Clinically, the lesions of type 2 segmental involvement are markedly more pronounced and superimposed on a milder, non-segmental, heterozygous manifestation of the same trait.² In the light of these concepts of mosaicism, we critically reviewed (previously published) antique illustrations of presumed “full blown” NF1 sufferers.^3–9 We have diagnosed as having mosaic/segmental NF1 the Indian man (“Homuncio”) in the “Monstrorum Historia”¹⁰ of the Italian naturalist and philosopher Ulisse Aldrovandi (1522-1605), the horned monster in “Des Monstres et Prodiges”¹¹ of the French surgeon Ambroise Paré (1510-1590), and the goitred woman in the “Buch der Natur”¹² of the German naturalist Conrad von Megenberg (1303-1374). Type 2 segmental manifestations of NF1 were recognisable in Buffon’s girl (1707-1788)¹³ and the “Wart Man” of Tilesius (1793).¹⁴