PTCH mutations in four Brazilian patients with holoprosencephaly and in one with holoprosencephaly-like features and normal MRI.

We report five Brazilian probands with PATCHED (PTCH) mutations and highly variable phenotypes with holoprosencephaly in four cases and holoprosencephaly-like facial features with a normal MRI in a fifth case. Three of our mutations were novel: Ala443Gly, Val751Gly, and Val908Gly. Two patients had the same mutation (Val908Gly), but were phenotypically different: alobar holoprosencephaly, absent nasal septum, and midline cleft lip-palate in one case, and lobar holoprosencephaly, macrocephaly, hypertelorism, clefting of the nose, severe microphthalmia, and a single maxillary central incisor in the other. One of our patients had a Thr1052Met mutation, holoprosencephaly-like facial features, and a normal MRI. Ming et al. [(2002); Hum Genet 110:297-301] reported an identical mutation, but with alobar holoprosencephaly.