Severe pulmonary emphysema in a girl with interstitial deletion of 2q24.2q24.3 including ITGB6

Abstract

Owing to the large size of chromosome 2, partial monosomy of the long arm of this chromosome gives rise to many specific phenotypes. We report on a 2-month-old girl with an interstitial deletion of 2q24.2q24.3, which was confirmed by microarray-based comparative genomic hybridization analysis. The patient showed delayed growth and mental retardation, early myoclonic seizures, and characteristic dysmorphic features including thick arched eyebrows, upslanting palpebral fissures, long eyelashes, depressed nasal bridge, short nose, long philtrum, small mouth, micrognathia, and low set ears. Her early myoclonic seizures were likely due to haploinsufficiency of SCN1A and SCN2A, which are included in the deletion region. When she experienced acute bronchopneumonia, she showed severe pulmonary emphysema. The deletion region of 2q24.2 includes the integrin beta6 gene (ITGB6), which may prevent acute lung injury and pulmonary emphysema. Many previously reported patients with deletions of 2q24.2 showed poor outcomes because of respiratory failure. These observations suggest the possibility of a strong relationship between haploinsufficiency of ITGB6 and pulmonary dysfunction.