Duplication Xq13.2–q21.1

In 2009, a de novo duplication of the Xq13.2q21.1 region was described. This 7 Mb duplication in a specific patient encompassed 23 known genes, including the X‑linked intellectual disability (XLMR) genes ATRX and SLC16A2, which influence cognitive development. The phenotype of this patient was similar to that described in more than 10 previously reported patients with overlapping Xq duplications. Detailed comparison of the clinical characteristics and the functions of genes located within the commonly duplicated regions in these patients led to the hypothesis that increased dosage of ATRX, and possibly other genes, contributes to the pathogenetic mechanism of this XLMR phenotype, resulting in intellectual disability, short stature, and genital abnormalities, including cryptorchidism and/or a small penis.

The patient described by Lugtenberg et al. (2009) had a duplication of Xq13.2q21.1, extending from approximately 72.4 to 79.6 Mb (within BAC clones CTD‑2003H23 to RP11‑608A14). This approximately 7 Mb duplication could not be detected by routine chromosomal analysis, nor retrospectively by a 500‑band karyotype. The patient exhibited many features also observed in another reported patient, including feeding difficulties in childhood, generalized hypotonia, psychomotor delay, intellectual disability, speech impairment, short stature, bilateral ptosis, high‑arched palate, low‑set ears, pectus excavatum, genu valgum, and cryptorchidism. The duplication in this patient further narrows the critical region responsible for the shared clinical features with the patient described by Lugtenberg.

• psychomotorické zaostávanie
• mentálne postihnutie rôznych stupňov
• nízky vzrast
• genitálne abnormality zahŕňajúce kryptorchizmus a/alebo malý penis
• v detstve problémy s kŕmením a prehĺtaním
• hypotónia
• problém s rečou
• bilaterálna ptóza
• tvárové črty - vysoko klenutéhé podnebie, nízko nasadené uši
• pectus excavatum