Bruck syndrome (BS) is an autosomal recessive syndromic form of osteogenesis 
imperfecta (OI) that is characterized by the additional presence of pterygium 
formation. We have recently shown that FKBP10 previously reported as a novel 
autosomal recessive OI gene also defines a novel Bruck syndrome locus (BKS3). In 
this manuscript, we extend our analysis to describe a mutation previously 
described in isolated OI patients and show that it results in BS phenotype in a 
Saudi family. More interestingly, we describe a novel FKBP10 mutation that 
results in isolated OI as well as BS phenotype in the same family. These 
results, combined with recently published work, confirm that FKBP10 is a 
bonafide BS locus and lay the foundation for future research into modifiers that 
underlie the phenotypic heterogeneity of FKBP10 mutations.