Clinical characteristics and genetic analysis of Feingold syndrome due to chromosome 2p24.3p24.2 microdeletion
Objective To explore the genetic etiology and clinical phenotype of Feingold syndrome due to chromosome 2p24.3p24.2 microdeletion.Methods The clinical data of a child admitted to Henan Provincial People's Hospital in November 2021 and diagnosed as Feingold syndrome type 1(FGLDS1)associated with chromosome 2p24.3p24.2 microdeletion were collected.The clinical and genetic variation characteristics of the patient were summarized,and 10 patients with chromosome 2p microdeletion reported until November 2022 were reviewed.Results The boy was 12 years and 5 months old.He presented with backward physical development,motor development retardation,low intelligence,special body and facial appearance,finger developmental deformity and other manifestations,accompanied by hyperactivity and aggressive behavior,impulsive irritability,self-injury and other behavior problems.The proband showed normal chromosome karyotype;the genome-wide copy number variant sequencing and trio-whole exome sequencing revealed a 2.61 Mb deletion at chromosome 2p24.3p24.2 region,and 10 genes including MYCN gene(exons 1 to 3)in the deleted region.The same deletion was not found in either of his parents.The genetic features of 11 cases(including this case)with chromosome 2p microdeletion were summarized,all of whom had insufficient haploid dosage of the MYCN gene due to chromosome 2p microdeletion,and the clinical manifestations of these 11 patients matched the clinical diagnosis of FGLDS1.Conclusion The proband is consistent with the clinical presentation of the typical Feingold syndrome,and the haploinsufficiency of the MYCN gene due to the microdeletion of chromosome 2 is the genetic etiology of the proband.