Temple–Baraitser syndrome: A rare and possibly unrecognized condition

Abstract

Temple-Baraitser syndrome, previously described in two unrelated patients, is the association of severe mental retardation and abnormal thumbs and great toes. We report two additional unrelated patients with Temple-Baraitser syndrome, review clinical and radiological features of previously reported cases and discuss mode of inheritance. Patients share a consistent pattern of anomalies: hypo or aplasia of the thumb and great toe nails and broadening and/or elongation of the thumbs and halluces, which have a tubular aspect. All patients were born to unrelated parents and occurred as a single occurrence in multiple sibships, suggesting sporadic inheritance from a de novo mutation mechanism. Comparative genomic hybridization in Patients 1, 2 and 3 did not reveal any copy number variations. We confirm that Temple-Baraitser syndrome represents a distinct syndrome, probably unrecognized, possibly caused by a de novo mutation in a not yet identified gene.

Report of a patient with Temple–Baraitser syndrome

“…The facial resemblance with myopathic appearance, mild hypertelorism, broad nasal bridge, short columella, long philtrum and down turned corners of the mouth is striking [Temple and Baraitser, 1991;Gabbet et al, 2008;Jacquinet et al, 2010]. Presence of epicanthal folds, previously reported in two other patients is noteworthy [Gabbet et al, 2008;Jacquinet et al, 2010]. Presence of pulmonary valve stenosis and atrial septal defect in our patient might also expand the phenotype.…”

“…Table I summarizes clinical findings in the previously reported TBS patients in comparison to the present report. The facial resemblance with myopathic appearance, mild hypertelorism, broad nasal bridge, short columella, long philtrum and down turned corners of the mouth is striking [Temple and Baraitser, 1991;Gabbet et al, 2008;Jacquinet et al, 2010]. Presence of epicanthal folds, previously reported in two other patients is noteworthy [Gabbet et al, 2008;Jacquinet et al, 2010].…”

“…However hypoplasia rather than aplasia of the hallux How to Cite this Article: nails were only seen in our patient while the others had total absence of the nail. Only one patient had unilateral aplasia of the thumb nail [Jacquinet et al, 2010]. Radiographic images demonstrating aplasia/hypoplasia on all phalanges and pesudoepiphyses of thumbs and toes are consistent in all patients [Temple and Baraitser, 1991;Gabbet et al, 2008;Jacquinet et al, 2010].…”

“…The condition was initially described in 1992 in a patient with severe intellectual disability and absence/hypoplasia of the thumb and hallux [Temple and Baraitser, 1991]. Since then, three additional patients have been reported [Gabbet et al, 2008;Jacquinet et al, 2010]. The consistent pattern shared by all patients in the literature is severe intellectual disability and a motor deficit with minor dysmorphic features and ray abnormalities like small/absent nails with elongation of thumbs and halluces.…”

“…Only one patient had unilateral aplasia of the thumb nail [Jacquinet et al, 2010]. Radiographic images demonstrating aplasia/hypoplasia on all phalanges and pesudoepiphyses of thumbs and toes are consistent in all patients [Temple and Baraitser, 1991;Gabbet et al, 2008;Jacquinet et al, 2010]. Presence of a proximally implanted and distally broadened thumb and long hallux is also a common feature [Gabbet et al, 2008;Jacquinet et al, 2010].…”