Intellectual disability (ID) is the most common diagnosis noted among children with genetic disorders. It causes social and economic burden to families and communities. The genetic causes are not completely understood, and there is significant heterogeneity. Recently, a new chromosomal X-linked syndrome was reported to cause ID. Four males were described from three families with ID, developmental delay, hypotonia, joint hypermobility, and relative macrocephaly. They all carried small, overlapping Xp11.22 deletions. To date, the described smallest region of overlapping deletion at this locus spanned ~ 430 kb) and included four genes (CENPVL1, CENPVL2, MAGED1, and GSPT2), which are proposed as the main drivers of the phenotype. We describe a male patient who matches the phenotype and contributes to defining a narrow phenocritical region at Xp11.22. We propose that GSPT2 loss-of-function might be the probable cause of the phenotypic features seen in these patients.

Intellectual disability (ID) is the most common diagnosis noted among children with genetic disorders. It causes social and economic burden to families and communities. The genetic causes are not completely understood, and there is significant heterogeneity. Recently, a new chromosomal X-linked s...