Array comparative genomic hybridisation analysis of boys with X‐linked hypopituitarism identifies a 3.9 Mb duplicated critical region at Xq27 containing SOX3

In our previous article,¹ we used array‐comparative genomic hybridisation (CGH) analysis to identify Xq26–q27 duplications in families with X‐linked hypopituitarism (XH). The array‐CGH assay was validated using affected male genomic DNA from two previously characterised XH families that carry Xq26–q27 duplications²,³ (fig 1B,C) and by interphase fluorescence in situ hybridisation (FISH) analysis (fig 2). Array‐CGH analysis of three novel XH families, A, B and C (fig 3), indicated that each of these contained a different Xq26–q27 duplication (fig 1D–G).

Recently, we repeated these array‐CGH experiments using a more extensive X chromosome array containing over 2000 bacterial artificial chromosome (BAC) clones.⁴ As expected, duplications were identified in males from the two previously characterised XH families.²,³ However, we have been unable to detect Xq26–q27 duplications in affected males from families A, B and C. Furthermore, repeated quantitative real‐time PCR experiments performed by an independent collaborator in a blinded assay detected SOX3 duplication in affected males from control families,²,³ but not in affected males from families A, B and C. On the basis of these new data, we now cannot replicate the observation of duplications in families A, B and C families that was published in our paper.