Premium
Identification of a novel homozygous ALX4 mutation in two unrelated patients with frontonasal dysplasia type‐2
Author(s) -
ElRuby Mona,
ElDin Fayez Alaa,
ElDessouky Sara H.,
Aglan Mona S.,
Mazen Inas,
Ismail Nora,
Afifi Hanan H.,
Eid Maha M.,
Mostafa Mostafa I.,
Mehrez Mennat I.,
Khalil Yasmin,
Zaki Maha S.,
Gaber Khaled R.,
AbdelHamid Mohamed S.,
AbdelSalam Ghada M. H.
Publication year - 2018
Publication title -
american journal of medical genetics part a
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.064
H-Index - 112
eISSN - 1552-4833
pISSN - 1552-4825
DOI - 10.1002/ajmg.a.38655
Subject(s) - hypertelorism , macrocephaly , corpus callosum , anatomy , encephalocele , dysgenesis , biology , craniofacial , cerebellar vermis , skull , medicine , pathology , genetics , cerebellum
We report two unrelated boys with frontonasal dysplasias type‐2 (FND‐2) who shared an identical novel homozygous ALX4 mutation c.291delG (p.Q98Sfs*83). Both patients presented with a large skull defect but one had bilateral parietal meningocele‐like cysts that lie along with the bony defect and increased in size with age. Scalp alopecia, hypertelorism, and clefted alae nasi were also detected in both of them. Furthermore, impalpable gonads were noted, being unilateral in one and bilateral in the other. Neuroimaging showed small dysplastic occipital lobes with dysgyria and midline subarachnoid cyst. Additional dysplastic corpus callosum and small cerebellar vermis were observed in one patient. Parietal foramina were noted in the parents of one patient. Our findings highlight the dosage effect of ALX4 and underscore the challenges of prenatal genetic counseling. Further, the indirect role of ALX4 in the development of the occipital lobe and posterior fossa is discussed.