Identification of a Novel Microdeletion Causative of Nance-Horan Syndrome

Authors

Mariana Lopez Martinolich
Hope Northrup
Pedro Mancias
Paul Hillman
Kavya Rao
Kate Mowrey

Publication Date

3-1-2022

Journal

Molecular Genetics and Genomics Medicine

Abstract

BACKGROUND: Nance-Horan syndrome (NHS) is a rare X-linked genetic disorder characterized by ophthalmologic and dental anomalies as well as dysmorphic facies. The clinical phenotype in males includes congenital cataracts, vision loss, microcornea, nystagmus, microphthalmia, glaucoma, screwdriver blade-shaped incisors, supernumerary maxillary incisors, diastema, delays, intellectual disability, and dysmorphic facies. With the evolution of array-CGH technology, a total of five kindreds with NHS have been reported in the medical literature with microdeletions encompassing the NHS gene rather than sequencing variants.

METHODS: The patient is a 19-year-old male born to non-consanguineous parents with a past medical history of bilateral congenital cataracts, nystagmus, poor vision, glaucoma, screwdriver blade-shaped incisors, global developmental delay, intellectual disability, bilateral sensorineural hearing loss, axial hypotonia, and bilateral foot contractures.

RESULTS: A chromosomal microarray (CMA) was performed and revealed a 1.83-Mb interstitial microdeletion at Xp22.2p22.13 (16,604,890-18,435,836) (GRCh37/hg19) that included NHS, CTPS2, S100G, TXLNG, RBBP7, REPS2, SCML1, RAI2, and SCML2.

CONCLUSION: Here, we report the second largest microdeletion causative of NHS which also encompasses the remaining four kindreds in hopes of offering a unique perspective at the clinical variability within NHS, investigate genes of interest, and expand the phenotype.

Keywords

Calcium-Binding Proteins, Cataract, Facies, Genetic Diseases, X-Linked, Glaucoma, Humans, Intellectual Disability, Male, Polycomb-Group Proteins, Tooth Abnormalities, microdeletion, Nance‐Horan syndrome, NHS

Comments

PMID: 35122698