Expanding the mutation spectrum in 182 Spanish probands with craniosynostosis: identification and characterization of novel TCF12 variants.

Craniosynostosis, caused by the premature fusion of one or more of the cranial sutures, can be classified into non-syndromic or syndromic and by which sutures are affected. Clinical assignment is a difficult challenge due to the high phenotypic variability observed between syndromes. During routine diagnostics, we screened 182 Spanish craniosynostosis probands, implementing a four-tiered cascade screening of FGFR2, FGFR3, FGFR1, TWIST1 and EFNB1. A total of 43 variants, eight novel, were identified in 113 (62%) patients: 104 (92%) detected in level 1; eight (7%) in level 2 and one (1%) in level 3. We subsequently screened additional genes in the probands with no detected mutation: one duplication of the IHH regulatory region was identified in a patient with craniosynostosis Philadelphia type and five variants, four novel, were identified in the recently described TCF12, in probands with coronal or multisuture affectation. In the 19 Saethre-Chotzen syndrome (SCS) individuals in whom a variant was detected, 15 (79%) carried a TWIST1 variant, whereas four (21%) had a TCF12 variant. Thus, we propose that TCF12 screening should be included for TWIST1 negative SCS patients and in patients where the coronal suture is affected. In summary, a molecular diagnosis was obtained in a total of 119/182 patients (65%), allowing the correct craniosynostosis syndrome classification, aiding genetic counselling and in some cases provided a better planning on how and when surgical intervention should take place and, subsequently the appropriate clinical follow up.

Screening for symptoms of obstructive sleep apnea in children with severe craniofacial anomalies: assessment in a multidisciplinary unit.

OBJECTIVE: To assess the incidence of airway obstruction symptoms and the presence of obstructive sleep apnea in children with severe craniofacial anomalies by a proactive screening program using a standard questionnaire and cardiorespiratory polygraphy. PATIENTS AND METHODS: Children with severe craniofacial anomalies referred to our paediatric airway unit from February 2001 to June 2011 were eligible to be included in this retrospective, single centre study. Symptoms of airway obstruction were proactively investigated using the shorter version of the Pediatric Sleep Questionnaire (PSQ). Obstructive sleep apnea was assessed by means of cardiorespiratory polygraphy. Demographic data and reason for referral were also recorded. Primary outcomes were the prevalence of symptoms of airway obstruction and OSA. RESULTS: 44 children (24 girls) with severe craniofacial anomalies (15 Crouzon, 13 Apert, 9 Goldenhar, 5 Treacher-Collins, 2 Pfeiffer) were included, at a mean age of 5 years (range 8 months to 14 years). Reason for referral was routine follow up in 30 patients and overt OSA symptoms and signs in the remaining 14. PSQ results showed symptoms of airway obstruction in 82% of patients, being snoring the most frequent symptom (64.1%) followed by apneas (33.3%). Polygraphic studies showed inconclusive results in 8 children (18.2%), normal apnea-hypopnea index (AHI) in 16 (36.4%), mild obstructive sleep apnea in 9 (20.4%), moderate in 4 (9.1%) and severe obstructive sleep apnea in 7 (15.9%). CONCLUSIONS: Children with craniofacial anomalies have a high prevalence of symptoms of airway obstruction and obstructive sleep apnea that support a proactive screening strategy in this highly selected population.