17q23.1q23.2 microdeletion syndrome is a condition caused by a small deletion of genetic material from chromosome 17. The deletion occurs at a location encompassing bands 23.1 to 23.2 on the long (q) arm of the chromosome. People with 17q23.1q23.2 microdeletion syndrome may have developmental delay, microcephaly, short stature, heart defects and limb abnormalities. Most cases are approximately 2.2 Mb in size and include the transcription factor genes TBX2 and TBX4 which have been implicated in a number of developmental pathways, including those of the heart and limbs.

17q23.1q23.2 microdeletion syndrome is characterized by developmental delay, microcephaly, short stature, heart defects and hand, foot and limb abnormalities. All individuals reported to date have had mild to moderate developmental delay, in particular delays in speech. Most have had heart defects, including patent ductus arteriosus or atrial septal defects. Limb abnormalities include long, thin fingers and toes, and hypoplasia (underdevelopment) of the patellae (knee caps). Scoliosis may also be present. Many patients have also had mild and unspecific unusual facial features.

The syndrome is caused by an interstitial deletion (a deletion that does not involve the ends of a chromosome) encompassing bands 23.1 to 23.2 on the long (q) arm of chromosome 17. Two transcription factors, TBX2 and TBX4, which belong to a family of genes implicated in a variety of developmental pathways including those of heart and limbs, are found within this 2.2Mb region. This suggests that they may play a part in the symptoms seen in this condition.

de novo origin, meaning that the deletion was new to the family.

The deletion can be identified by comparative genomic hybridization (CGH) microarray and fluorescence in situ hybridization (FISH).