A novel 47.2 Mb duplication on chromosomal bands Xq21.1–25 associated with mental retardation

• Novel Xq21.1–25 duplication, harbored 231 RefSeq genes, including 32 OMIM genes.
• A 2-year-old girl with facial dysmorphism, mental retardation and short stature
• Ten genes in the duplication interval were associated with mental retardation.
• Association of mental retardation with X chromosome duplication

We present array comparative genomic hybridization (aCGH) characterization of a novel Xq21.1–25 duplication in a 2-year-old girl with facial dysmorphism, mental retardation and short stature. Analysis of aCGH results revealed a 47,232 kb duplication region that harbored 231 RefSeq genes, including 32 OMIM genes. Ten genes (i.e., ZNF711, SRPX2, RAB40AL, MID2, ACSL4, PAK3, UBE2A, UPF3B, CUL4B, and GRIA3) in the duplication interval have been associated with mental retardation. We discuss the genotype–phenotype correlation in this case. Our case provides evidence for an association of mental retardation with X chromosome duplication.