ABSTRACT
Objective:To analyze the clinical phynotypes of fetuses with 22q11.2 microduplications.Method:Eleven fetuses were diagnosed with 22q11.2 microduplications among 2 969 cases who underwent prenatal chromosomal microarray analysis from January 2016 to February 2020. The phenotypes, indications for invasive prenatal diagnosis, genetic results, pregnancy outcomes and postnatal clinical presentation were analyzed.Results:There were 6 cases diagnosed with classic 3.0 Mb microduplication (DiGeorge and velocardiofacial syndromes, DGS/VCFS) in the 22q11.2, 1 case with 1.5 Mb proximal microduplication and 4 cases with distal small segment microduplication (E-H). Out of 11 fetuses with 22q11.2 microduplications,7 cases were inherited, 2 cases was de novo and data were not available for 2 cases. Vicular septal defect and anencephalu were diagnosed by ultrasonography in 2 cases,fetal growth restriction was diagnosed in 2 cases,no any abnormalities were found in remaining 7 cases. Seven cases(3 cases of classic 3.0 Mb microduplication, 1 case of proximal microduplication and 3 cases of distal small segment microduplication) were delivered at full-term;and pregnancy was terminated in 4 cases. Seven infants were followed up after birth, 4 infants were normal, 3 showed abnormal phenotypes.Conclusion:The clinical phenotypes after birth of fetuses with 22q11.2 microduplication are diverse. Prenatal genetic counseling is necessary,so that pregnant women and their families can fully understand the possible clinical phenotypes and make informed choices.
ABSTRACT
OBJECTIVE@#To explore strategies of prenatal genetic testing for fetuses featuring abnormal skeletal development.@*METHODS@#Clinical data of 17 fetuses with skeletal dysplasia was collected. The results of genetic testing and outcome of pregnancy were analyzed.@*RESULTS@#For 12 fetuses, the femur-to-foot length ratio was less than 0.9. Thirteen fetuses had a positive finding by genetic testing. One fetus was diagnosed with chromosomal aneuploidy, three were diagnosed with microdeletion/microduplications, and nine were diagnosed with hereditary bone diseases due to pathological variants of FGFR3, COL1A2, GPX4 or ALPL genes.@*CONCLUSION@#For fetuses with skeletal dysplasia characterized by short femur, in addition to chromosomal karyotyping and microarray analysis, sequencing of FGFR3 and other bone disease-related genes can improve the diagnostic rate.