**2.3 FISH analyses with commercially available probe**

A FISH study using the Vysis Williams Region Probe - LSI ELN SpectrumOrange/LSI D7S486, D7S522 SpectrumGreen was carried out on the metaphase preparations from all 14 patients, as recommended by the manufacturer (Abbott, Rungis, France).

The Williams Region Probe consists of a probe of approximately 180 kb in size for *ELN*, *LIMK1* and the D7S613 locus located in band 7q11.23, labeled in Spectrum Orange, and a control probe for the region containing loci D7S486 and D7S522 located in band 7q31, labeled in Spectrum Green.
