Consanguinity and pregnancy outcomes in a multi-ethnic, metropolitan European population.

Objective: The aim of the present study was to assess the risk of major anomalies in the offspring of consanguineous couples, including data on the prenatal situation.

Methods: Over 20 years (1993-2012), 35,391 fetuses were examined by prenatal sonography. In 675 cases (1.

Fetal Aneuploidy Detection by Cell-Free DNA Sequencing for Multiple Pregnancies and Quality Issues with Vanishing Twins.

Non-invasive prenatal testing (NIPT) by random massively parallel sequencing of maternal plasma DNA for multiple pregnancies is a promising new option for prenatal care since conventional non-invasive screening for fetal trisomies 21, 18 and 13 has limitations and invasive diagnostic methods bear a higher risk for procedure related fetal losses in the case of multiple gestations compared to singletons. In this study, in a retrospective blinded analysis of stored twin samples, all 16 samples have been determined correctly, with four trisomy 21 positive and 12 trisomy negative samples. In the prospective part of the study, 40 blood samples from women with multiple pregnancies have been analyzed (two triplets and 38 twins), with two correctly identified trisomy 21 cases, confirmed by karyotyping.

Noninvasive prenatal detection of chromosomal aneuploidies using different next generation sequencing strategies and algorithms.

Objective: Here we describe the successful application of massively parallel sequencing for noninvasive prenatal detection of trisomy 21. In addition, for the detection of a broader spectrum of fetal aneuploidies, a target enrichment approach was successfully tested.

Methods: The circulating cell-free DNA was prepared from 53 maternal blood samples and analysed using Illumina's sequencing systems Genome Analyzer(IIx) and HiSeq2000, respectively.

'Normal' nuchal translucency: a justification to refrain from detailed scan? Analysis of 6858 cases with special reference to ethical aspects.

Objective: To assess the prevalence and detection rate of major anomalies (MAs) by applying first trimester anomaly scan (FTAS) including first trimester fetal echocardiography (FTFE) to all fetuses and discuss ethical implications.

Methods: The study group included 6879 consecutive fetuses with known outcome of pregnancy (follow-up: 98%), 6565 with 'normal' nuchal translucency (NT) (≤ P95), 314 with 'increased' NT (> P95). All fetuses received FTAS/FTFE.

Small supernumerary marker chromosomes 1 with a normal phenotype.

Small supernumerary marker chromosomes (sSMCs) are a major problem in prenatal cytogenetic diagnostics. Over two-thirds of cases carrying an sSMC derived from chromosome 1 are associated with clinical abnormalities. We report 3 further cases of such sSMCs that did not show any clinical abnormalities.

Molecular cytogenetic characterisation of an interstitial deletion 12p detected by prenatal diagnosis.

Objectives: Deletions in the short arm of chromosome 12 are rare structural aberrations. Till now only ten patients with interstitial deletions are described in the literature. Here, we report on the first case detected by prenatal diagnosis.

Prenatal diagnosis and molecular cytogenetic characterisation of a small de novo interstitial duplication 16q11.2-q13.

We describe the first prenatally detected case of a small de novo interstitial duplication of chromosome 16q. This chromosomal aberration is extremely rare. Amniocentesis was indicated by advanced maternal age only.

Slow progression of ataxia-telangiectasia with double missense and in frame splice mutations.

Ataxia-telangiectasia (A-T) is caused by mutations of the ATM gene, the product of which is involved in the regulation of cellular responses to radiation damage. Ataxia usually starts in early childhood but a delayed age at onset and slower rate of neurological deterioration has been found for some patients with variant A-T. Only few patients have been documented to survive into the 4th decade.

Prenatal diagnosis of fetal trisomy 6 mosaicism and phenotype of the affected newborn.

The first case of a fetal trisomy 6 mosaicism proven at 25 weeks of gestation by analysis of fetal urine cells is described. Chromosomal analysis was indicated by an ultrasonographically diagnosed heart defect at 21 weeks of gestation. The chromosomal aberration was detected in amniotic fluid cells while fetal blood cells showed a normal chromosome set.

Small supernumerary marker chromosomes (SMCs): genotype-phenotype correlation and classification.

Small supernumerary marker chromosomes (SMCs) are present in about 0.05% of the human population. In approximately 30% of SMC carriers (excluding the approximately 60% SMC derived from one of the acrocentric chromosomes), an abnormal phenotype is observed.

Ring chromosome 6 in three fetuses: case reports, literature review, and implications for prenatal diagnosis.

Prenatal and postnatal findings in three fetuses with a ring chromosome 6 are presented, and the literature of this rare cytogenetic disorder is reviewed. The described fetuses illustrate the broad spectrum of the clinical manifestation of ring chromosome 6. In one fetus, the disorder was diagnosed incidentally by a routine amniocentesis due to advanced maternal age.