Intrauterine phenotype features of fetuses with 7q11.23 microduplication syndrome

Objective: To share our experience on prenatal diagnosis of 7q11.23 microduplication syndrome and to further delineate the fetal phenotypes of the syndrome.

Methods: A retrospective study was conducted to evaluate seven cases of dup7q11.23 syndrome diagnosed prenatally by chromosomal microarray (CMA). Clinical data were reviewed, including maternal characteristics, indications for prenatal diagnosis, sonographic findings, CMA results, pregnancy outcomes and follow-ups.

Results: Seven cases, including 2 pairs of MCDA twins, were prenatally identified with dup7q11.23 syndrome. The most common prenatal sonographic features were ventriculomegaly, low-lying conus medullaris, and dilated ascending aorta. All 7 fetuses presented with typical 7q11.23 duplications (1.40-1.55 Mb). Parental chromosome analysis was performed in four pairs of parents, and indicated that the duplications of Case 6 and 7 were inherited from their asymptomatic mother.

Conclusion: Our case series suggest that prenatal features of dup7q11.23 cases are diversified, with ventriculomegaly and low-lying conus medullaris being the most common intrauterine phenotypes. Additionally, cleft palate, dilated ascending aorta, and renal abnormalities were also observed, and should be taken into consideration in subsequent studies.