De novo truncating mutations in ASXL3 are associated with a novel clinical phenotype with similarities to Bohring-Opitz syndrome

Original research article by M.N. Bainbridge et al. (2013).

Read the article here.

This article compares four children with ASXL3 gene changes with children with Bohring-Opitz syndrome. Bohring-Opitz syndrome is typically caused by changes in a different gene, ASXL1. Researchers now believe that the two genes may have similar roles in growth and development.

The two genetic conditions have many features in common, including small size throughout pregnancy (IUGR) and small size at birth, feeding difficulties in infancy, slow growth, differences in finger position (may appear to be bent outward, rather than straight), developmental delay with missed milestones, and intellectual disability. One child with an ASXL3 change died at 9 months of age. The gene changes in all four children with ASXL3 changes were de novo, meaning that the changes were not present in either parent and were brand new in the child.

Several features specific to Bohring-Opitz syndrome were not seen in the children with ASXL3 changes. These are elbow and wrist flexion problems, vision problems, and early fusion of bones in the skull that cause the head to be shaped differently. None of the four children in the study had these features.