Microduplication in the 2p16.1p15 chromosomal region linked to developmental delay and intellectual disability

• Published in: Molecular cytogenetics Vol. 11; no. 1; pp. 39 - 6
• Main Authors: Lovrecic, Luca, Gnan, Chiara, Baldan, Federica, Franzoni, Alessandra, Bertok, Sara, Damante, Giuseppe, Isidor, Bertrand, Peterlin, Borut
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 20-06-2018; BioMed Central; BMC
• Subjects: 2p16.1p15; Age; Array CGH, microduplication; Birth weight; Case Report; Child development deviations; Chromosome abnormalities; Chromosomes; Complications and side effects; Congenital diseases; Developmental delay; Developmental disabilities; Duplication; Gastroesophageal reflux; Genetic aspects; Genetic counseling; Genomes; Genomics; Genotype & phenotype; Intellectual disabilities; Macrocephaly; Mental retardation; Microcephaly; Molecular karyotyping; Patients; Phenotypes; Risk factors; Speech; Syndactyly; Ultrasonic imaging; Visual impairment; France; Italy; Array CGH, microduplication; Duplication; Molecular karyotyping; Developmental delay; 2p16.1p15; Macrocephaly
• ISSN: 1755-8166; 1755-8166
• DOI: 10.1186/s13039-018-0388-y

Several patients with the 2p16.1p15 microdeletion syndrome have been reported. However, microduplication in the 2p16.1p15 chromosomal region has only been reported in one case, and milder clinical features were present compared to those attributed to 2p16.1p15 microdeletion syndrome. Some additional cases were deposited in DECIPHER database.
In this report we describe four further cases of 2p16.1p15 microduplication in four unrelated probands. They presented with mild gross motor delay, delayed speech and language development, and mild dysmorphic features. In addition, two probands have macrocephaly and one a congenital heart anomaly. Newly described cases share several phenotype characteristics with those detailed in one previously reported microduplication case.
The common features among patients are developmental delay, speech delay, mild to moderate intellectual disability and unspecific dysmorphic features. Two patients have bilateral clinodactyly of the 5th finger and two have bilateral 2nd-3rd toes syndactyly. Interestingly, as opposed to the deletion phenotype with some cases of microcephaly, 2 patients are reported with macrocephaly. The reported cases suggest that microduplication in 2p16.1p15 chromosomal region might be causally linked to developmental delay, speech delay, and mild intellectual disability.