The semilethal skeletal malformation syndrome campomelic dysplasia (CD) with or without XY sex reversal is caused by mutations within the SOX9 gene on 17q24.3 or by chromosomal aberrations (translocations, inversions or deletions) with breakpoints outside the SOX9 coding region. The previously published CD translocation breakpoints upstream of SOX9 fall into two clusters: a proximal cluster with breakpoints between 50-300 kb and a distal cluster with breakpoints between 899-932 kb. Here, we present clinical, cytogenetic and molecular data from two novel CD translocation cases. Case 1 with karyotype 46,XY,t(1;17)(q42.1;q24.3) has characteristic symptoms of CD, including mild tibial bowing, cryptorchidism and hypospadias. By standard fluorescence in situ hybridization (FISH) and by high-resolution fiber FISH, the 17q breakpoint was mapped 375 kb from SOX9, defining the centromeric border of the proximal breakpoint cluster region. Case 2 with karyotype 46,X,t(Y;17)(q11.2;q24.3) has the acampomelic form of CD and complete XY sex reversal. By FISH and somatic cell hybrid analysis, the 17q breakpoint was mapped 789 kb from SOX9, defining the telomeric border of the distal breakpoint cluster region. We discuss the structure of the 1 Mb cis-control region upstream of SOX9 and the correlation between the position of the 14 mapped translocation breakpoints with respect to disease severity and XY sex reversal.

We report an isolated case of a girl aged three years six months with Duchenne muscular dystrophy. Analysis of the patient's DNA with a probe covering the DNA gene revealed no deletion. Dystrophin, studied in biopsied muscle from the patient, using antidystrophin antibody in combination with immunofluorescence, was nearly completely absent. In this sporadic case of female muscular dystrophy, the identification of dystrophin-deficient muscle fibers made it possible to establish an accurate diagnosis of DMD affected female.