Prenatal diagnosis of 17q12 duplication and deletion syndrome in two fetuses with congenital anomalies

Taiwan J Obstet Gynecol. 2014 Dec;53(4):579-82. doi: 10.1016/j.tjog.2014.05.004.

Abstract

Objective: The objective of this study was to characterize the genetic abnormalities in two fetuses with congenital anomalies in prenatal screening.

Materials and methods: The mother of Fetus 1 was 26 years old and had a second trimester serum screening that indicated the fetus was at low risk. The prenatal ultrasound and magnetic resonance imaging (MRI) at 28 weeks of gestation showed mild ventriculomegaly, microcephaly, and agenesis of the corpus callosum. The mother of Fetus 2 was 25 years old and also had a second trimester serum screening that indicated the fetus was at low risk. The prenatal ultrasound at 32 weeks of gestation showed the presence of hyperechogenic and enlarged kidneys with multicystic renal dysplasia bilaterally and a persistent left superior vena cava (PLSVC). Both pregnant women underwent cord blood samplings because of the abnormal imaging results. Karyotype analysis revealed normal results in the two fetuses. Chromosome microarray analysis (CMA) was then performed to provide genetic analysis of the cord blood and parental blood samples. Ultimately, the pregnancies were both terminated.

Results: CMA detected a 1.56-Mb duplication at 17q12 in Fetus 1 and a 1.93-Mb deletion of 17q12 in Fetus 2. Both the duplicated and deleted regions included the HNF1B and LHX1 genes. Neither the duplication nor deletion was inherited from the parents.

Conclusion: This study is the first to report the prenatal diagnosis of a 17q12 duplication syndrome. Our results further confirmed that genes in this region, including HNF1B and LHX1, are essential for normal brain and kidney development, and also indicated some genes that may be associated with the cardiovascular abnormality. Combined with imaging examination, the use of CMA will improve the diagnosis of submicroscopic chromosomal aberrations in fetuses with congenital anomalies.

Keywords: 17q12 deletion; 17q12 duplication; chromosome microarray analysis; prenatal diagnosis.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / diagnosis*
  • Abnormalities, Multiple / genetics
  • Adult
  • Chromosome Deletion*
  • Chromosome Duplication*
  • Chromosomes, Human, Pair 17*
  • Female
  • Genetic Markers
  • Genetic Testing*
  • Hepatocyte Nuclear Factor 1-beta / genetics
  • Humans
  • LIM-Homeodomain Proteins / genetics
  • Pregnancy
  • Prenatal Diagnosis*
  • Syndrome
  • Transcription Factors / genetics

Substances

  • Genetic Markers
  • HNF1B protein, human
  • LHX1 protein, human
  • LIM-Homeodomain Proteins
  • Transcription Factors
  • Hepatocyte Nuclear Factor 1-beta