A case of 5p15.1-5p15.33 duplication and literature review / 中华神经科杂志

ABSTRACT

Objective:To analyze the clinical and genetic features of the children with 5p15.1-5p15.33 duplication at the end of the short arm of chromosome 5 (5p).Methods:Clinical data of a 5p15.1-5p15.33 duplicative patient diagnosed in the Department of Pediatric Intensive Care Unit of West China Second University Hospital of Sichuan University in July 2021 were collected, and the characteristics of the patients of 5p duplication syndrome reported in the literatures were summarized and analyzed.Results:The boy was 1 year and 5 months old at the time of admission. The main clinical manifestations included growth restriction and developmental delay after birth, accompanied by craniofacial deformities. At 7 months old, he was diagnosed as epilepsy due to convulsive limbs. At present, he is 2 years old, still has recurrent convulsions, can not raise his head, sit alone, crawl and talk, with hypotonia. Repeated cranial magnetic resonance imaging showed agenesis of the corpus callosum. The child′s parents had normal phenotypes. His copy number variation sequencing results showed partial overlap of chromosome 5p15.1-5p15.33 (chr51934522-18905656), which was determined as pathogenic copy number variation according to copy number variations evaluation criteria, and no abnormality was detected in his parents. According to the retrieval strategy set in this study, 10 literatures (all in English, reporting 17 cases) were retrieved, and a total of 22 5p duplication syndrome patients (including this case and 4 cases included in databases) were included. Seventeen of the 22 patients were younger than 14 years old with a onset age of 7 (0, 18) years, and the male to female ratio was about 1.1∶1. Among the 22 patients, craniofacial malformation was found in 19 patients, developmental disorder in 18, bone/muscle dysplasia in 15, autism in 11, attention deficit hyperactivity disorder in 9, mental retardation in 8, obesity in 5, epilepsy in 5, congenital heart dysplasia in 2, hypotonia in 4, strabismus/hyperopia in 2, and corpus callosum dysplasia, endocrine dysfunction, inguinal hernia as well as umbilical hernia in 1, respectively. There were 19 cases of multiple malformation and 3 cases of single malformation.Conclusions:5p15.1-5p15.33 duplication may be the genetic cause of this child. Facial malformation, developmental delay, skeletal/muscular dysplasia, intellectual disability, autism spectrum disorder and attention deficit hyperactivity disorder are the main clinical phenotypes of 5p copy number duplication. Corpus callosum dysplasia may be an extended phenotype of chromosome duplication at this location.