Constitutional microdeletions affecting 3q13.2q13.31 are rare and attempts for genotype-phenotype correlations have only recently been made in a cohort of 28 patients. The major phenotypic features of this rare syndrome are hypotonia, developmental delay, and facial anomalies. In this study, we report on a male infant with a novel reciprocal 3.671 Mb microduplication at the genomic region 3q13.2q13.31 associated with dysmorphic features and multiple congenital anomalies. The current patient was investigated by high-resolution array comparative genomic hybridization (aCGH). This is the first report of a microduplication 3q13.2q13.31 that shares a lot of common clinical features with those carrying the microdeletion. The 3q13.2q13.31 duplicated region in our patient contains nine dosage sensitive genes, amongst them the genes ATG3, CCDC80, KIAA2018, NAA50, ZDHHC23, DRD3, ZBTB20, GAP43, LSAMP. As it is the case for many other well-described reciprocal deletion/duplication syndromes, some have very different clinical features (Williams-Beuren deletion syndrome, WBS/WBS triplication) [Somerville et al. (2005); N Engl J Med 353:1694-1701], while others share similar phenotypic features (22q11.2 microdeletion/microduplication) [Portnoi (2009); Eur J Med Genet 52:88-93]. In conclusion, we describe the main phenotypic features of a possibly novel microduplication 3q13.2q13.31 syndrome. Additionally five of the dosage-sensitive genes and BOC gene are suggested to be responsible for the main phenotypic features. Evaluation of multiple patients with the microduplication is needed for full delineation of this syndrome.
Keywords: 3q11q23 microdeletion syndrome; 3q11q23 microduplication syndrome; congenital anomalies; dosage sensitive genes; hypotonia.
© 2013 Wiley Periodicals, Inc.