[1] Univ Roma La Sapienza, Dept Expt Med & Pathol, I-00161 Rome, Italy
[2] Biomed Sci Pk San Raffaele, I-00128 Rome, Italy
[3] Natl Inst Dent & Cranifacial Res, Craniofacial & Skeletal Dis Branch, Dept Hlth & Human Serv, NIH, Bethesda, MD 20892 USA
[4] Univ Texas Hlth Sci Ctr Houston, Brown Fdn Inst Mol Med, Houston, TX 77030 USA