Expression of p53, p63 and p73 in the orofacial region of human embryos.

We studied p53, p63, p73 protein expression in the orofacial region of five human embryos aged 7-18 weeks of intrauterine development using a three-step immunohistochemical method. Expression of proteins in various locations was evaluated semiquantitatively. A decrease in p53, p63 and p73 proteins occured in the 13-week-old material with the exception of the tooth germ where a drop in p73 appeared in the ninth week.