This is an example of 4p- in which a small part of the short arm of chromosome 4 has been lost. This is an example of a deletion. Wolf's syndrome is very rare. Affected children are small, with microcephaly and abnormal facies. There are cardiac, renal, and genital abnormalities. Most are stillborn or die in infancy.

Another rare deletion is 5p- resulting in Cri-du-chat syndrome. Affected infants have a low birth weight and a distinctive mewing, cat-like cry. Children have facial anomalies and are mentally retarded.