Identification of 1q21.1 microduplication in a family: A case report

BACKGROUNDCopy number variation (CNV) has become widely recognized in recent years due to the extensive use of gene screening in developmental disorders and epilepsy research. 1q21.1 microduplication syndrome is a rare CNV disease that can manifest as multiple congenital developmental disorders, autism spectrum disorders, congenital malformations, and congenital heart defects with genetic heterogeneity.CASE SUMMARYWe reported a pediatric patient with 1q21.1 microduplication syndrome, and carried out a literature review to determine the correlation between 1q21.1 microduplication and its phenotypes. We summarized the patient's medical history and clinical symptoms, and extracted genomic DNA from the patient, her parents, elder brother, and sister. The patient was an 8-mo-old girl who was hospitalized for recurrent convulsions over a 2-mo period. Whole exon sequencing and whole genome low-depth sequencing (CNV-seq) were then performed. Whole exon sequencing detected a 1.58-Mb duplication in the CHR1:145883867-147465312 region, which was located in the 1q21.1 region. Family analysis showed that the pathogenetic duplication fragment, which was also detected in her elder brother's DNA originated from the mother.CONCLUSIONWhole exon sequencing combined with quantitative polymerase chain reaction can provide an accurate molecular diagnosis in children with 1q21.1 microduplication syndrome, which is of great significance for genetic counseling and early intervention.

Automated summary

This study reported a pediatric patient with 1q21.1 microduplication syndrome and conducted a literature review to determine the correlation between 1q21.1 microduplication and its phenotypes. Genomic DNA was extracted from the patient and her family members, and a 1.58 Mb duplication in the 1q21.1 region was identified using whole exon sequencing. The study concluded that whole exon sequencing combined with quantitative polymerase chain reaction can provide an accurate molecular diagnosis in children with 1q21.1 microduplication syndrome, which is important for genetic counseling and early intervention.