Skin Markers of X-Linked Dominant Chondrodysplasia Punctata

Abstract

To the Editor.— In the October 1978 issue of theArchives(114:1479-1483, 1978), Dr Curth reconsidered her interesting case report of 1949 1 dealing with the association of follicular atrophoderma and chondrodysplasia punctata. With regard to cause, Dr Curth now suggests either an X-linked dominant gene that is lethal in hemizygous males or an autosomal dominant gene with sex-limited expression. The following arguments are advanced to show that the first possibility is more likely. The concept of X-linked dominant chondrodysplasia punctata was proposed because of two facts. 2,3 First, some patients with chondrodysplasia punctata show widespread atrophic skin lesions and alopecia, and occasionally also pigmentary disturbances that may easily be confused with incontinentia pigmenti of the Bloch-Sulzberger type. This pattern of skin lesions suggests functional X-chromosome mosaicism. Consequently, in involved areas the X chromosome carrying the mutant gene should be active, whereas in uninvolved skin the normal X chromosome should be