Our results indicate that these three syndromes form part of a clinical spectrum resulting from a heterogeneous group of mutations in the L1 gene. Molecular analysis of the patient was recently described in Tarleton et al. Thus, the deletion occurred as a do novo event. The patient does not appear to have clinical or laboratory findings other that those typically associated with fragile X syndrome, suggesting that the deletion does not remove other contiguous genes. This report describes the phenotype of the patient, including psychological studies.
Clinical manifestations tend to have considerable intrafamilial and interfamilial variability.
Previous linkage studies had localized the gene responsible for BOR syndrome to a broad region of chromosome 8q. These markers are within 1 cM of one another. Thus, the apparent selective inactivation of the full mutant FMR-1 allele appears to have resulted in limited expression with normal intellect. Cytogenetic analyses of some of the cases have indicated an association between chromosomal rearrangements involving 7q21.3-q22 and ectrodactyly. Analysis indicated that higher numbers of fragile X gene carriers reported having irregular menses and other gynecological complications.