Opitz trigonocephaly C syndrome in a boy with a de novo balanced reciprocal translocation t(3;18)(q13.13;q12.1)

Abstract

Opitz trigonocephaly C syndrome (OTCS) is a multiple congenital anomaly syndrome characterized by trigonocephaly, mental retardation, a typical facial appearance, redundant skin, joint and limb abnormalities, and visceral anomalies. We describe a patient with the manifestations of OTCS who also had a de novo balanced reciprocal translocation t(3;18)(q13.13q12.1). His phenotype is a mild form with mild developmental delay and no severe visceral anomalies. Our findings suggest the possible existence of a new locus responsible for OTCS either on 3q13.13 or 18q12.1.

Opitz C syndrome: Trigonocephaly, mental retardation and craniofacial dysmorphism

“…The syndrome has no chromosomal abnormality defined in the usual karyotype suggesting that this disorder may be a microdeletion syndrome which is cytogenetically detectable only with fluorescence in situ hybridization (FISH) that can show in some cases a genetic alteration by subtelomeric deletion in the long arm of different chromosomes like 3, 9 and 11 [11,12]; our case shows translocation at the chromosome 11 like other previous cases reported [13]. The syndrome has a complex phenotype due to the haploinsufficiency of one or more genes, in some patients was found that the CD96 gene is disrupted, identifying a missense mutation [14]; these mutations may cause a disease by interfering with adhesion and growth of the cells; recently were found some CD96 aberrations caused by genetic translocation [15]; the disorder is a heterogeneous genetic disease which occurs mainly sporadically, although there are some rare cases of familial occurrence that have been described; if the chromosome analysis performed in both parents is normal, this condition indicates that the translocation occurred for the first time by a new mutation. In our case, the parents and the siblings of the patient, all of them have normal stature and there are no craniofacial dysmorphic features, actually these parents no longer wish for new children and they rejected their cytogenetic studies; therefore it is not known if one of them is carrier of a genetic anomaly, if both parents were normal, the recurrence risk was low at 1%.…”

Bohring–Opitz (Oberklaid–Danks) syndrome: clinical study, review of the literature, and discussion of possible pathogenesis

“…These are: (1) trigonocephaly; (2) primary or secondary microcephaly; (3) flammeus nevus; (4) prominent eyes; (5) micro-or retrognathia; (6) abnormal palate; (7) typical 'BOS posture' (BOS posture of the upper limbs is defined as having three out of four features: exorotation and/or adduction of the shoulders; flexion at the elbows; flexion at the wrists; and ulnar deviation of the wrists and/or fingers at the MCP joints. ); (8) feeding difficulties; (9) IUGR; and (10) severe/profound learning difficulties or death before this can be adequately assessed.…”

“…9 Mutations in the TACTILE gene have been implicated as a cause of Opitz C syndrome, which has overlapping features with BOS, after one patient was found to have a balanced translocation causing disruption of this gene 10 and a missense mutation was subsequently identified in another. 11 However, the clinical phenotype of these two patients is not typical of BOS and mutations of this gene have been excluded in patients with BOS, including several of those described here.…”

Craniosynostosis genetics: The mystery unfolds

“…Chromosomal alterations are important causative mechanisms of the syndromic forms of craniosynostosis accounting for at least 10% of the cases. [25–27] Table 1 lists the different conditions along with underlying genetic defect. In craniosynostosis-type Mcgillivray, mutation in the TK1 portion of FGFR2 was found.…”