Optical Genome Mapping Identifies a Novel Unbalanced Translocation Between Chromosomes 4q and 6q Leading to Feeding Difficulties and Hypotonia in a Neonate: A Case Report

Abstract

Ying Wang, Shaohua Bi, Xiaoqing Shi, Liying Dai Division of Neonatology, Anhui Provincial Children’s Hospital, Hefei, Anhui, 230051, People’s Republic of ChinaCorrespondence: Liying Dai, Division of Neonatology, Anhui Province Children’s Hospital, No. 39, Wangjiang East Road, Baohe District, Hefei, Anhui, 230051, People’s Republic of China, Email [email protected]: Optical Genome Mapping (OGM) technology has garnered growing interest for the identification of chromosomal structural variations (SVs), particularly complex ones that are implicated in genetic diseases in humans. In this study, we performed genetic diagnostics on a neonatal patient who presented with feeding difficulties, hypotonia, and an atrial septal defect. We utilized a combination of trio-whole exome sequencing and OGM for our analysis. The results revealed an unbalanced translocation between maternal chromosomes 4 and 6 in the proband, ogm[GRch38]t(4:6)(q35.2;q25.3), resulting in a 2.8 Mb deletion at the 4q35 terminal and a 10.2 Mb duplication at the 6q25 terminal. In summary, this study highlights how OGM, in conjunction with other genetic approaches, can unveil the genetic etiology of complex clinical syndromes. Neonatal patients often exhibit low specific phenotypes, underlining the significance of SV detection.Keywords: optical genome mapping, unbalanced translocation, copy number variations, neonatal diseases

Keywords

• optical genome mapping
• unbalanced translocation
• copy number variations
• neonatal diseases