The ears are low-set, abnormally shaped, and frequently have narrow external auditory canals and preauricular tags.
Syndactyly, hypertelorism, and cardiac anomalies occur often.
Mental and physical development is markedly retarded.
Deletion of the short arm of chromosome 4 (4p) results in variable intellectual disability; individuals with larger deletions are usually more severely affected.
Manifestations also may include epilepsy, a broad or beaked nose, midline scalp defects, ptosis and colobomas, cleft palate, delayed bone development, and, in boys, hypospadias and cryptorchidism.
Some patients with Wolf-Hirschhorn syndrome also have immune deficiency.
Chromosomal deletion syndromes result from loss of parts of chromosomes.
They may cause severe congenital anomalies and significant intellectual and physical disability.
Chromosomal deletion syndromes are rarely suspected prenatally but may be incidentally discovered at that time if karyotyping is done for other reasons.Postnatal diagnosis is suspected by clinical appearance and is confirmed by karyotyping, if the deletion is relatively large, or by other cytogenetic techniques such as fluorescent in situ hybridization or microarray analysis.Chromosomal deletion syndromes typically involve larger deletions, that are typically visible on karyotyping.Syndromes involving smaller deletions (and additions) that affect one or more contiguous genes on a chromosome and are not visible on karyotyping are considered microdeletion and duplication syndromes.Deletion of the end of the short arm of chromosome 5 (5p—usually paternal) is characterized by a high-pitched, mewing cry, closely resembling the cry of a kitten, which is typically heard in the immediate neonatal period, lasts several weeks, and then disappears.Affected neonates are hypotonic and have low birth weight, microcephaly, a round face with wide-set eyes, downward slanting of the palpebral fissures (with or without epicanthal folds), strabismus, and a broad-based nose.