Metacarpophalangeal profile pattern analysis in a further patient with a novel ARID1B variant.

Acral clinical and radiographic characteristics of a further patient with Coffin-Siris syndrome (CSS), which is caused by mutations in the ARID1B gene, encoding a subunit of the BAF-complex, are here described. Metacarpophalangeal profile pattern analysis (MCPPPA) of the present proband and other two known ARID1B mutated individuals has been performed for the first time, demonstrating hands brachydactyly. In this novel study, the utility of an accurate appendicular radiographic examination and MCPPPA in this congenital condition is highlighted. The MCPPPA could be considered in the clinical practice, to better study the hand skeletal morphology in patients with a syndrome characterized by limb defects, including CSS.