Recent reports have described a distinct and recurrent pattern of systemic 
malformation that associates craniosynostosis and neurodevelopmental 
abnormalities with many clinical features of the Marfan syndrome (MFS), an 
autosomal dominant disorder of the extracellular microfibril caused by defects 
in the gene encoding fibrillin-1, FBN1 (ref. 8). Additional common findings 
include other craniofacial anomalies, hypotonia, obstructive apnea, foot 
deformity, and congenital weakness of the abdominal wall. So far, only 11 cases 
have been reported precluding the assignment of definitive diagnostic criteria. 
While it remains unclear whether these cases represent a discrete clinical 
entity with a single aetiology, they have been pragmatically grouped under the 
rubric Marfanoid-craniosynostosis or Shprintzen-Goldberg syndrome (SGS). Because 
of the significant clinical overlap between MFS and SGS, we proposed that they 
may be caused by allelic mutations. We now report two SGS patients who harbour 
mutations in FBN1. While it remains unclear whether these mutations are 
sufficient for the clinical expression of the entire SGS phenotype, these data 
suggest a role for fibrillin-1 in early craniofacial and central nervous system 
development. Our recent observation that FBN1 transcript is expressed as early 
as the 8-cell stage of human embryogenesis is consistent with this hypothesis.