[Identification of a 17q25.3 duplication in a Chinese patient with global developmental delay and multiple congenital...

To delineate the clinical features,inheritance pattern, and genotype-phenotype correlation of a Chinese patient with a 17q25.3 duplication.

Whole exome sequencing(WES), chromosomal microarray analysis (CMA), chromosomal karyotyping and fluorescence in situ hybridization (FISH) were employed for the analysis of the proband and his family members.

A 5.7 Mb duplication at 17q25.3→qter was identified by WES and CMA in the 4-year-old boy with multiple congenital anomalies, which was classified as a clinically pathogenic variant. This duplication was confirmed by FISH, and was inherited from his unaffected mother who carried a balanced translocation. Further study revealed that his grandmother also carried the balanced translocation but had gestated three healthy children and had no abortion history. His uncle also carried the balanced translocation, while his aunt was normal.

Above results have enriched the clinical phenotypes of 17q25.3 duplication. Genetic counseling was provided for the family. P4HB, ACTG1, BAIAP2 and TBCD genes may underlie the clinical features for the 17q25.3 duplication.