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. 
What is (are) 17q23.1q23.2 microdeletion syndrome ?