Wolf Hischhorn Chromosome Abnormality by Andrew Waters Tim Lyle Heather Edmondson David Grkovic

Wolf Hirschhorn DEFINITION-A chromosomal disorder characterized by 4p monosomy resulting in certain facial dysmorphic features and neurological manifestations.

Epidemiology incidence: rare (120 cases reported worldwide) age of onset: newborn (dysmorphic features) RISK FACTORS sporadic in a majority of cases 13% of cases due to parental chromosomal aberrations, i.e., translocation F > M

Genetic Defect deletion of some of the genetic material of the short arm of chromosome 4 deletion of band 4p16 is required for full phenotypic expression also referred to as Wolf-Hirschhorn Syndrome

Facial Dysmorphic Features Head and neck: Cranial asymmetry, microcephaly, high forehead, occasional midline scalp defect, micrognathia, facial angiomas, long face, midfacial hypoplasia Ears: Deeply seated malformed and poorly differentiated ears with lobeless pinnae, narrow external canals, and preauricular dimples or skin tags. Eyes: Hypertelorism, highly arched eyebrows, downward or upward slanting palpebral fissures, strabismus, coloboma of the iris, corectopia, and blepharoptosis. Nose: Beaked nose with wide bridge, prominent glabella, short philtrum, and epicanthal folds. Mouth and oral structures: Carp-shaped mouth with downturned corners, cleft lip and/or palate, thick lower lip, highly-arched palate, and hypodontia.

Neurological Manifestations profound mental retardation severe psychomotor retardation weak cry in infancy seizures

Other Manifestations hypospadias hypoplastic Mullerian derivatives low birthweight (mean = 2,015 gm) postnatal growth retardation underdeveloped dermal ridges and low ridge count

Pictures The website says Children “with Wolf-Hirschhorn syndrome (46,XY,del[4p]). Note the wide-spaced eyes and repaired cleft lip." (Wolf-Hirschhorn syndrome. 14 May n.htm)

Karyotype In this karyotype a small part of the p-arm of chromosome 4 has been lost. This is an example of a deletion. (Wolf-Hirschhorn syndrome. 14 May