Adrenal hypoplasia congenita (AHC) is an X-linked disorder characterized by primary adrenal insufficiency. Hypogonadotropic hypogonadism (HHG) is frequently associated with this disorder but is thought not to be caused by the low adrenal androgen levels due to adrenal hypoplasia. It is uncertain whether there are two distinct yet physically linked genes responsible for AHC and HHG or a single gene responsible for both diseases. AHC can occur as a part of a contiguous deletion syndrome together with Duchenne muscular dystrophy (DMD) and/or glycerol kinase deficiency (GKD). From the analysis of deletions, the following gene order has been deduced: Xpter-AHC-GKD-DMD-cen. An AHC critical region of 200-500 kilobases has been defined by physical mapping and partially overlaps with a 160-kilobase dosage-sensitive sex (DSS) reversal critical region. The DAX-1 (DSS-AHC critical region on the X, gene 1) gene was isolated and found to encode a new member of the nuclear hormone receptor family. Here we report that DAX-1 is deleted in 14 patients and point mutations were found in the coding region in DNA from 12 unrelated individuals. All AHC patients over 14 years old and with only point mutations in DAX-1 were also diagnosed with HHG, confirming that the DAX-1 gene is responsible for both X-linked AHC and HHG. But in four sporadic cases and a single familial case, no point mutations were found, suggesting genetic heterogeneity or differential expression of DAX-1.

Most mutations in the dystrophin gene create a frameshift or a stop in the mRNA and are associated with severe Duchenne muscular dystrophy. Exon skipping that naturally occurs at low frequency sometimes eliminates the mutation and leads to the production of a rescued protein. We have achieved persistent exon skipping that removes the mutated exon on the dystrophin messenger mRNA of the mdx mouse, by a single administration of an AAV vector expressing antisense sequences linked to a modified U7 small nuclear RNA. We report the sustained production of functional dystrophin at physiological levels in entire groups of muscles and the correction of the muscular dystrophy.

UMD-DMD France is a knowledgebase developed through a multicenter academic effort to provide an up-to-date resource of curated information covering all identified mutations in patients with a dystrophinopathy. The current release includes 2,411 entries consisting in 2,084 independent mutational events identified in 2,046 male patients and 38 expressing females, which corresponds to an estimated number of 39 people per million with a genetic diagnosis of dystrophinopathy in France. Mutations consist in 1,404 large deletions, 215 large duplications, and 465 small rearrangements, of which 39.8% are nonsense mutations. The reading frame rule holds true for 96% of the DMD patients and 93% of the BMD patients. Quality control relies on the curation by four experts for the DMD gene and related diseases. Data on dystrophin and RNA analysis, phenotypic groups, and transmission are also available. About 24% of the mutations are de novo events. This national centralized resource will contribute to a greater understanding of prevalence of dystrophinopathies in France, and in particular, of the true frequency of BMD, which was found to be almost half (43%) that of DMD. UMD-DMD is a searchable anonymous database that includes numerous newly developed tools, which can benefit to all the scientific community interested in dystrophinopathies. Dedicated functions for genotypebased therapies allowed the prediction of a new multiexon skipping (del 45-53) potentially applicable to 53% of the deleted DMD patients. Finally, such a national database will prove to be useful to implement the international global DMD patients' registries under development. Hum Mutat 30,[934][935][936][937][938][939][940][941][942][943][944][945]