Diagnostic value of exome and whole genome sequencing in craniosynostosis

<strong>Background.</strong> Craniosynostosis, the premature fusion of one or more cranial sutures, occurs in ~1 in 2250 births, either in isolation or as part of a syndrome. Mutations in at least 57 genes have been associated with craniosynostosis, but only a minority of these are inclu...

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Detalhes bibliográficos
Principais autores: Miller, K, Twigg, S, McGowan, S, Phipps, J, Fenwick, A, Johnson, D, Wall, S, Noons, P, Rees, K, Tidey, E, Craft, J, Taylor, J, Goos, J, Swagemakers, S, Mathijssen, I, van der Spek, P, Lord, H, Lester, T, Abid, N, Cilliers, D, Hurst, J, Morton, J, Sweeney, E, Weber, A, Wilson, L, Wilkie, A
Formato: Journal article
Publicado em: BMJ Publishing Group 2016
Descrição
Resumo:<strong>Background.</strong> Craniosynostosis, the premature fusion of one or more cranial sutures, occurs in ~1 in 2250 births, either in isolation or as part of a syndrome. Mutations in at least 57 genes have been associated with craniosynostosis, but only a minority of these are included in routine laboratory genetic testing. <strong>Methods.</strong> We utilised exome or whole genome sequencing to seek a genetic cause in a cohort of 40 subjects with craniosynostosis, selected by clinical or molecular geneticists as being high priority cases, and in whom prior clinically-driven genetic testing had been negative. <strong>Results.</strong> We identified likely associated mutations in 15 patients (37.5%), involving 14 different genes. All genes were mutated in single families, except for IL11RA (2 families). We classified the other positive diagnoses as follows: commonly mutated craniosynostosis genes with atypical presentation (EFNB1, TWIST1); other core craniosynostosis genes (CDC45, MSX2, ZIC1); genes for which mutations are only rarely associated with craniosynostosis (FBN1, HUWE1, KRAS, STAT3); and known disease genes for which a causal relationship with craniosynostosis is currently unknown (AHDC1, NTRK2). In two further families, likely novel disease genes are currently undergoing functional validation. In 5 of the 15 positive cases, the (previously unanticipated) molecular diagnosis had immediate, actionable consequences for either genetic or medical management (mutations in EFNB1, FBN1, KRAS, NTRK2, STAT3). <strong>Conclusions.</strong> This substantial genetic heterogeneity, and the multiple actionable mutations identified, emphasises the benefits of exome/whole genome sequencing to identify causal mutations in craniosynostosis cases for which routine clinical testing has yielded negative results.