Supplementary Material for: Microdeletion 15q26.2qter and Microduplication 18q23 in a Patient with Prader-Willi-Like Syndrome: Clinical Findings

<br>The small interstitial deletion in the long arm of chromosome 15 causing Prader-Willi/Angelman syndrome is well known, whereas cases that report terminal deletions in 15q in association with the Prader-Willi-like phenotype are very rare. By using GTG-banding analysis, metaphase FISH, MLPA analysis, and genome-wide array CGH, we detected an unbalanced translocation involving a microdeletion of the distal part of 15q and a microduplication of the distal part of 18q. The unbalanced translocation was found in a boy that was referred with clinical suspicion of Prader-Willi syndrome. In the 15q-deleted region, 23 genes have been identified, and 13 of them are included in the OMIM database. Among these, the deleted <i>IGFR1</i>,<i> MEF2A</i>,<i> CHSY1</i>, and <i>TM2D3 </i>genes could contribute to the patient's phenotype. Seven genes are included in the duplicated chromosome segment 18q, but only one <i>(CTDP1)</i> is present in the OMIM database. We suggest that the deleted chromosome segment 15q26.2qter may be responsible for the phenotype of our case and may also be a candidate locus of Prader-Willi-like syndrome.