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Microdeletion Syndromes
Published in Merlin G. Butler, F. John Meaney, Genetics of Developmental Disabilities, 2019
Gopalrao V. N. Velagaleti, Nancy J. Carpenter
Wolf–Hirschhorn syndrome is caused by a deletion of the short arm of chromosome 4 extending from 4p16 to the terminus. About 75% of the deletions are uncomplicated and de novo, about 12% are due to unusual chromosomal rearrangements such as ring chromosomes or mosaicism for the deletion, and the remaining 13% result from segregation of balanced translocations in the parents (134). According to one report, there are at least 20 cases of WHS that are inherited (135). Among the de novo deletions, there appears to be a preponderance of paternal deletions (142,143). Because the majority of the unbalanced translocations are maternal in origin (144) and the de novo cases are paternal in origin, it was suggested that imprinting might play a role in the phenotypic expression of WHS (143).
An unusual ophthalmic presentation of Wolf-Hirschhorn syndrome
Published in Ophthalmic Genetics, 2021
Gökhan Çelik, Bilge Batu Oto, Osman Kızılay, Oğuzhan Kılıçarslan, Handan Hakyemez Toptan
Wolf-Hirschhorn Syndrome is developmental disorder characterized by craniofacial abnormalities, heart defects, skeletal and urogenital defects. The incidence of WHS is about 1/50.000–100.000 in live births and is twice more often in females (1). WHS is caused by deletion of the short arm of 4th chromosome. A recent study suggested neural crest motility and migration defects during development as a pathophysiology for WHS (2). Each patient presents with a unique combination of WHS characteristics, the severity of the phenotype in WHS depends on the extent of deletion area (3). Ophthalmic manifestations occur in approximately 40% of the patients (1). Refractive errors, epicanthus, hypertelorism, strabismus, ptosis, proptosis, colobomas of the eyelid and microphthalmia can be seen. Glaucoma, microcornea and iris coloboma can be observed. Foveal hypoplasia, colobomas of retina, choroid and optic nerve are the manifestations of posterior segment (4).
Congenital cavitary optic disc anomaly and Axenfeld’s anomaly in Wolf-Hirschhorn syndrome: A case report and review of the literature
Published in Ophthalmic Genetics, 2018
Mohsin H. Ali, Nathalie F. Azar, Vinay Aakalu, Felix Y. Chau, Javaneh Abbasian, Pete Setabutr, Irene H. Maumenee
Wolf-Hirschhorn syndrome is a genetic syndrome characterized by a deletion of chromosome 4p16.3. We describe the ocular phenotype of an affected patient, including the rare descriptions and photographs of Axenfeld’s anomaly, megalopapilla, and cavitary optic disc anomaly in this condition.