Unbalanced translocation 6p/16q (partial monosomy 6p and trisomy 16q): prenatal diagnosis and cytogenetics

Puhl, Alexander G.; Zelazny, Julia; Galetzka, Danuta; Skala, Christine; Frey-Mahn, Gabriele; Wellek, Brigitte; Koelbl, Heinz

doi:10.1016/j.ejogrb.2010.02.034

« Previous Next »European Journal of Obstetrics & Gynecology and Reproductive Biology
Volume 150, Issue 2 , Pages 119-125, June 2010

Unbalanced translocation 6p/16q (partial monosomy 6p and trisomy 16q): prenatal diagnosis and cytogenetics☆

Alexander G. Puhl
- Department of Obstetrics and Gynaecology, University Medicine, Langenbeckstr. 1, 55131 Mainz, Germany
- Corresponding author. Tel.: +49 6131 173912; fax: +49 6131 173405.
Julia Zelazny
- Department of Obstetrics and Gynaecology, University Medicine, Langenbeckstr. 1, 55131 Mainz, Germany
Danuta Galetzka
- Institute of Human Genetics, University Medicine, Mainz, Germany
Christine Skala
- Department of Obstetrics and Gynaecology, University Medicine, Langenbeckstr. 1, 55131 Mainz, Germany
Gabriele Frey-Mahn
- Institute of Human Genetics, University Medicine, Mainz, Germany
Brigitte Wellek
- Institute of Human Genetics, University Medicine, Mainz, Germany
Heinz Koelbl
- Department of Obstetrics and Gynaecology, University Medicine, Langenbeckstr. 1, 55131 Mainz, Germany

Received 13 November 2009; received in revised form 29 January 2010; accepted 10 February 2010. published online 26 February 2010.

Abstract

Unbalanced translocation 6p/16q in one fetus is a very rare event and the prenatal sonographic findings have never been published before. We will give a short overview of the literature along with a case report focussing on prenatal ultrasound features and molecular cytogenetic analysis.

Case description

A 21-year-old primigravid woman presented with a singleton pregnancy at 19 weeks’ gestation. The fetus revealed a mild hydrocephalus, a ventricular septal defect (VSD), a Dandy–Walker malformation as well as an intrauterine growth retardation (IUGR) and limb anomalities. MLPA analysis from amniotic fluid cells showed an unbalanced translocation from the subtelomeric region of chromosome 6p to the subtelomeric region of chromosome 16q. Karyotype of the fetus was 46, XX.ishder(6)t(6;16)(p2?5;q?13)(pVYS246A+, pVYS228B−, pVYS229A+). Despite the karyotype the mother decided not to interrupt pregnancy. The fetus died in utero within the 39th week of gestation and was delivered vaginally after labour induction, with a birth weight of 1815g.

Prenatal FISH and MLPA studies can be very important to help outline the chromosomal area of deletion and duplication and the sonographic findings forebode the cytogenetic region of interest.

Subsequent to the processing of the case, a complete Medline search was conducted to review previous cases with similar genetic alterations.

Keywords: Monosomy 6p, Trisomy 16q, Pregnancy, Amniocentesis, Unbalanced translocation