- Subtle radiographic findings of achondroplasia in patients with Crouzon syndrome with acanthosis nigricans due to an Ala391Glu substitution in FGFR3. Schweitzer, D.N., Graham, J.M., Lachman, R.S., Jabs, E.W., Okajima, K., Przylepa, K.A., Shanske, A., Chen, K., Neidich, J.A., Wilcox, W.R. Am. J. Med. Genet. (2001)