1/3. Novel and recurrent EBP mutations in X-linked dominant chondrodysplasia punctata.chondrodysplasia punctata (CDP) is a heterogeneous group of skeletal dysplasias characterized by stippled epiphyses. A subtype of CDP, X-linked dominant chondrodysplasia punctata (CDPX2), known also as Conradi-Hunermann-Happle syndrome, is a rare skeletal dysplasia characterized by short stature, craniofacial defects, cataracts, ichthyosis, coarse hair, and alopecia. The cause of CDPX2 was unknown until recent identification of mutations in the gene encoding Delta(8),Delta(7) sterol isomerase emopamil-binding protein (EBP). Twelve different EBP mutations have been reported in 14 patients with CDPX2 or unclassified CDP, but with no evidence of correlation between phenotype and nature of the mutation. To characterize additional mutations and investigate possible phenotype-genotype correlation, we sequenced the entire EBP gene in 8 Japanese individuals with CDP; 5 of them presented with a CDPX2 phenotypes. We found EBP mutations in all 5 CDPX2 individuals, but none in non-CDPX2 individuals. Three of these CDPX2 individuals carried novel nonsense mutations in EBPand the other two, separate missense mutations that had been reported also in different ethnic groups. Our results, combined with previous information, suggest all EBP mutations that produce truncated proteins result in typical CDPX2, whereas the phenotypes resulted from missense mutations are not always typical for CDPX2. patients with nonsense mutations showed abnormal sterol profiles consistent with a defect in Delta(8), Delta(7) sterol isomerase. X-inactivation patterns of the patients showed no skewing, an observation that supports the assumption that inactivation of the EBP gene occurs at random in affected individuals.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/3. Wagner's vitreoretinal degeneration with generalized epiphyseal dysplasia.Wagner's vitreoretinal degeneration, midline facial defects and a moderate generalized epiphyseal dysplasia defined radiologically were encountered in a boy and his father. The familial nature of the condition and its autosomal dominant inheritance are described. Suggestions are made that patients said to have Wagner's disease differ in no way radiologically from cases diagnosed as having Stickler's syndrome.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/3. Absent chondrodysplasia punctata in a male with an Xp terminal deletion involving the putative region for CDPX1 locus.This is a follow-up report on a male patient with a 46,Y,r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean -5.6 S.D.).- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |