Recurrent 2q13 microduplication encompassing MALL, NPHP1, RGPD6, and BUB1 associated with autism spectrum disorder, intellectual disability, and liver disorder

Abstract

Objective: We present recurrent 2q13 microduplication in a family with autism spectrum disorder (ASD), intellectual disability, and liver disorder.

Case report: A 45-year-old woman and her 52-year-old husband were referred for genetic counseling because of mental and liver disorders in their two sons and their planning for prenatal diagnosis of familial disorders in the future pregnancy. She and her husband were normal and healthy, but their 21-year-old elder son had suffered from ASD, severe intellectual disability, poor motor function, liver cirrhosis, and esophageal varices, and their 19-year-old younger son had suffered from ASD, mild intellectual disability, poor balance and coordination, hepatosplenomegaly, fatty liver, and mild liver cirrhosis. The karyotypes of the parents and sons were normal. Array comparative genomic hybridization of the family revealed a 686.5-kb 2q13 microduplication encompassing MALL, NPHP1, RGPD6, and BUB1 in the elder brother, a 658.9-kb 2q13 microduplication encompassing MALL, NPHP1, RGPD6, and BUB1 in the younger brother, and an 83.83-kb 2q13 microduplication encompassing NPHP1 in the asymptomatic father.

Conclusion: Recurrent phenotypic abnormality in the family with normal karyotype should include a differential diagnosis of pathogenic copy-number variations.

Keywords: 2q13 duplication; autism spectrum disorder; intellectual disability; liver cirrhosis.