We present the first report of chromosomal rearrangement involving chromosomes 4, 10 and 12. The proband was a 42-year-old woman with severe mental retardation and multiple congenital anomalies. The most striking physical anomalies were upper limb contractures resulting in distal arthrogryposis. As upper limb flexion contractures have been previously reported in individuals with partial distal 10q deletion, this sign should be considered as part of the clinical manifestations of 10q25 --> qter monosomy.