Developmental retardation due to paternal 5q/11q translocation in a Chinese infant: clinical, chromosomal and microarray characterization

ABSTRACT

Although it is known that the parental carriers of chromosomal translocation are considered to be at high risk for spontaneous abortion and embryonic death, normal gestation and delivery remain possible. This study aims to investigate the genetic factors of a Chinese infant with multiple malformations and severe postnatal development retardation. In this study, the routine cytogenetic analysis, chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) analysis were performed. Conventional karyotype analyses revealed normal karyotypes of all family members. CMA of the DNA of the proband revealed a 8.3Mb duplication of 5q35.1-qter and a 6.9Mb deletion of 11q24.3-qter. FISH analyses verified a paternal tiny translocation between the long arm of chromosomes 5 and 11. Our investigation serves to provide important information on genetic counselling for the patient and future pregnancies in this family. Moreover, the combined use ofCMAand FISH is effective for clarifying pathogenically submicroscopic copy number variants.