Haploinsufficiency of BCL11A associated with cerebellar abnormalities in 2p15p16.1 deletion syndrome

Mol Genet Genomic Med. 2017 May 22;5(4):429-437. doi: 10.1002/mgg3.289. eCollection 2017 Jul.

Abstract

Background: Chromosome 2p15p16.1 deletion syndrome is a rare genetic disorder characterized by intellectual disability (ID), neurodevelopmental delay, language delay, growth retardation, microcephaly, structural brain abnormalities, and dysmorphic features. More than 30 patients with 2p15p16.1 microdeletion syndrome have been reported in the literature.

Methods: Molecular analysis was performed using microarray-based comparative genomic hybridization (array CGH). Clinical characteristics and brain magnetic resonance imaging features of these patients were also reviewed.

Results: We identified four patients with ID, neurodevelopmental delay, brain malformations, and dysmorphic features; two patients with 2p15p16.1 deletions (3.24 Mb, 5.04 Mb), one patient with 2p16.1 deletion (1.12 Mb), and one patient with 2p14p16.1 deletion (5.12 Mb). Three patients with 2p15p16.1 deletions or 2p16.1 deletions encompassing BCL11A,PAPOLG, and REL showed hypoplasia of the pons and cerebellum. The patient with 2p14p16.1 deletion, which did not include three genes showed normal size and shape of the cerebellar hemispheres and pons.

Conclusion: The zinc finger transcription factor BCL11A associated with the BAF chromatin remodeling complex has been identified to be critical for neural development and BCL11A haploinsufficiency is closely related to cerebellar abnormalities.

Keywords: BCL11A; cerebellar abnormalities; chromosome 2p15p16.1 deletion syndrome; chromosome 2p16.1 deletion; intellectual disability; neurodevelopmental delay; structural brain abnormality..