Testis development in the absence of SRY: chromosomal rearrangements at SOX9 and SOX3.

Duplications in the ~2 Mb desert region upstream of SOX9 at 17q24.3 may result in familial 46,XX disorders of sex development (DSD) without any effects on the XY background. A balanced translocation with its breakpoint falling within the same region has also been described in one XX DSD subject. We analyzed, by conventional and molecular cytogenetics, 19 novel SRY-negative unrelated 46,XX subjects both familial and sporadic, with isolated DSD. One of them had a de novo reciprocal t(11;17) translocation. Two cases carried partially overlapping 17q24.3 duplications ~500 kb upstream of SOX9, both inherited from their normal fathers. Breakpoints cloning showed that both duplications were in tandem, whereas the 17q in the reciprocal translocation was broken at ~800 kb upstream of SOX9, which is not only close to a previously described 46,XX DSD translocation, but also to translocations without any effects on the gonadal development. A further XX male, ascertained because of intellectual disability, carried a de novo cryptic duplication at Xq27.1, involving SOX3. CNVs involving SOX3 or its flanking regions have been reported in four XX DSD subjects. Collectively in our cohort of 19 novel cases of SRY-negative 46,XX DSD, the duplications upstream of SOX9 account for ~10.5% of the cases, and are responsible for the disease phenotype, even when inherited from a normal father. Translocations interrupting this region may also affect the gonadal development, possibly depending on the chromatin context of the recipient chromosome. SOX3 duplications may substitute SRY in some XX subjects.

Constitutional ring chromosome 11 mosaicism in a Wilms tumor patient: Cytogenetic, molecular and clinico-pathological studies.

We report on a boy with three cell lines: 46,XY, r(11)(p15.5,q25)[90]/45,XY,-11 [8]/47,XY, r(11)(p15.5,q25)x2[2], with minor anomalies and mental retardation who developed asynchronous bilateral Wilms tumors (WTs). Array comparative genomic hybridization (CGH) performed on peripheral blood leukocytes of the patient led to the identification of a constitutional duplication of 4.8 Mb at 11p15.5-11p15.4. This duplication was found to involve the chromosome of paternal origin, and occurred in tandem on the ring chromosome 11. Despite the constitutive duplication of the paternal 11p15 chromosome region, the patient showed no sign of Beckwith-Wiedemann syndrome. However, the molecular characterization of the two neoplasias was consistent with their independent origin and showed that they arose from the two distinct cellular clones with the ring chromosome, indicating that this anomaly is likely to have caused the patient's susceptibility to WT development.

Shprintzen-Goldberg omphalocele syndrome: a new patient with an expanded phenotype.

Shprintzen and Goldberg [1979] described a new autosomal dominant syndrome characterized by omphalocele, scoliosis, pharyngeal and laryngeal hypoplasia, mild dysmorphic face, and learning disabilities. This condition was described in a father and three daughters, one of whom died in infancy, probably of airway narrowing. Here, we report on a second observation of this syndrome in a 6-year-old patient. In our case, omphalocele, imperforate anus, and feeding impairment were the main clinical problems in the neonatal period. Scoliosis appeared during the fourth year of age. The facial appearance is similar to the original patients and additional clinical findings are described which expand the phenotypic spectrum.