Macular and optic nerve hypoplasia in chromosome 2p partial trisomy

The 2p duplication syndrome is a rare clinically heterogeneous disorder that arises from non-recurrent chromosomal rearrangements involving ~6 Mb up to ~90 Mb. The patients are characterized by a wide range of symptoms, including developmental delay, intellectual disability, distinctive facial features, congenital heart defects, and various ophthalmic manifestations.

We report a male newborn with maternally inherited unbalanced translocations resulting in partial trisomy of chromosome 2p (33.9 Mb) - 46,XY,der(10)t(2;10)(p22.3;p1?5)dmat. Fluorescence in situ hybridization and chromosomal microarray analyses confirmed three copies of 2p25.3-p22.3 region, encompassing 51 known disease-causing genes. The patient presented with low birth weight, ventricular septal defect, camptodactyly of the 3rd digit of the left hand and mild early feeding problems. Ophthalmological assessment revealed macular and optic nerve hypoplasia. MRI demonstrated hypoplasia of the optic chiasm and optic nerves, and partial agenesis of falx cerebri.

We describe macular and optic nerve hypoplasia in a patient with a novel chromosomal rearrangement resulting in 2p partial trisomy and provide an overview of 17 previously reported cases presenting ocular abnormalities. A broad variability of ophthalmological phenotypes has been observed, further expanded by the current report.