Patients with typical GCPS or PHS who have demonstrated GLI3 mutations may be excluded from this study. Patients with phenotypes and disorders with a high risk/benefit ratio such as late-onset, neurodegenerative, psychiatric, and cancer-predisposition disorders will be excluded from participation. Similarly, patients who are medically fragile or unable to tolerate travel to the NIH CC will not routinely be eligible for participation. Probands who are adults and decisionally-impaired are ineligible if they do not have a legal guardian who has authority to sign a consent form on their behalf.