The Liebenberg syndrome was first described in 1973 in a five- generation 
family. A sixth generation was added in 2001, and in 2009 a hitherto unknown 
branch of the same family with similar anomalies extended the family tree 
significantly. This article describes the clinical findings and illustrates the 
abnormalities with radiographs and three-dimensional computed tomography scans. 
We discuss the genetic abnormality that causes Liebenberg syndrome, the genomic 
rearrangement at the PITX1 locus on chromosome 5.The structural variations seem 
to result in an ectopic expression of paired-like homeodomain transcription 
factor 1 (PITX1) in the forelimb causing a partial arm-to-leg transformation in 
these patients.