2q31.1 Microdeletion Syndrome

2q31.1 microdeletion syndrome is a well-defined and clinically recognisable syndrome characterized by moderate to severe developmental delay, short stature, facial dysmorphism and variable limb defects.

Epidemiology

It has been reported in 20 patients.

Clinical description

Dysmorphic features include microcephaly, downslanting palpebral fissures, flat and long philtrum, micrognathia and low-set and dysplastic ears. The spectrum of limb defects ranges from monodactylous ectrodactyly, brachydactyly and syndactyly to camptodactyly. The lower limbs tend to be more often and more severely affected than the upper limbs.

Etiology

This microdeletion was identified by comparative genomic hybridization (CGH) microarray and its size is variable. The critical region encompasses the HOXD genes, haploinsufficiency of which results in the skeletal phenotype.