Microdeletion 8q22.2-q22.3 in a 40-year-old male

Abstract

Background: Interstitial deletions at chromosome 8q22.2-q22.3 have been rarely reported in the literature. To date, six patients have been described in the literature with deletions varying in size from 1.36 Mb to 6.44 Mb. These patients range in age from early childhood to early adulthood. The interstitial deletion phenotype has been described to involve moderate to severe intellectual disability, seizures and a distinct facial phenotype. We report on a 40-year-old male with a 3.351 Mb deletion at chromosome 8q22.2-q22.3 who presents with moderate intellectual disability, autism spectrum disorder, childhood seizure disorder, congenital heart defect and hearing loss. He is the oldest known patient to date.

Methods: Array comparative genomic hybridization (aCGH) was performed on DNA extracted from peripheral blood.

Conclusion: This is the first report of an individual with chromosome 8q22.2-q22.3 interstitial deletion associated with congenital heart disease and hearing loss. Haploinsufficiency of the GRHL2 gene contained within the microdeletion is proposed as a candidate genetic mechanism for this patient's hearing loss.

Keywords: 8q22.2-q22.3 microdeletion; Congenital heart disease; GRHL2; Hearing loss; Intellectual disability.