Confined placental mosaicism revisited: Impact on pregnancy characteristics and outcome.

Objectives: We wanted to re-evaluate the influence of confined placental mosaicism subtypes (type 2 and type 3) on pregnancy characteristics and outcome.

Material And Methods: From July 2009 to December 2015, 5512 chorionic villus samplings were performed in our Fetal Medicine Center. Conventional karyotyping was performed after long-term and short-term cultured villi to define type 2 or type 3 confined placental mosaicisms.

Evaluation of Quantitative Fluorescence in situ Hybridization for Relative Measurement of Telomere Length in Placental Mesenchymal Core Cells.

Background: Reduced telomere length in placental mesenchymal core cells has been reported during pregnancies complicated by intrauterine growth restriction. To estimate telomere length, a precise, accurate and reproducible technique must be used.

Objective: We evaluated the characteristics of a quantitative fluorescence in situ hybridization (Q-FISH) technique for measuring relative telomere length in placental mesenchymal core cells.

Prenatal diagnosis using array-CGH: a French experience.

Array-CGH or Chromosomal Microarray Analysis (CMA) is increasingly used in prenatal diagnosis throughout the world. However, routine practices are very different among centers and countries, regarding CMA indications, design and resolution of microarrays, notification and interpretation of Copy Number Alterations (CNA). We present our data and experience from our Fetal Medicine Center on 224 prospective prenatal diagnoses.

Reduced placental telomere length during pregnancies complicated by intrauterine growth restriction.

Objectives: Recent studies have shown that telomere length was significantly reduced in placentas collected at delivery from pregnancies complicated by intrauterine growth restriction secondary to placental insufficiency. Placental telomere length measurement during ongoing pregnancies complicated by intrauterine growth restriction has never been reported. This was the main objective of our study.

A homozygous balanced reciprocal translocation suggests LINC00237 as a candidate gene for MOMO (macrosomia, obesity, macrocephaly, and ocular abnormalities) syndrome.

Macrosomia, obesity, macrocephaly, and ocular abnormalities syndrome (MOMO syndrome) has been reported in only four patients to date. In these sporadic cases, no chromosomal or molecular abnormality has been identified thus far. Here, we report on the clinical, cytogenetic, and molecular findings in a child of healthy consanguineous parents suffering from MOMO syndrome.

Proportion of parents agreeing to delay fetal karyotyping until the third trimester of pregnancy in cases with an indication.

Objective: To assess the extent to which couples who could benefit from fetal karyotyping during the first or second trimester would agree to delay the examination until the third trimester.

Methods: In this prospective monocentric study, the same physician suggested to some couples to delay fetal karyotyping until the third trimester.

Results: 458 couples participated in this study.

An unusual chromosome 22q11 deletion associated with an apparent complementary ring chromosome in a phenotypically normal woman.

We report an unusual chromosome 22q11 deletion associated with an apparent complementary ring chromosome in a phenotypically normal woman with a family medical history of 22q11 deletion. Using peripheral blood samples, conventional karyotyping, Fluorescence In Situ Hybridization (FISH) analysis on metaphase spreads and oligo array-based comparative genomic hybridization (oligo array-CGH) were performed. After conventional cytogenetic examination, the chromosome formula was as follows: 47,XX,+r(?)[16]/46,XX[6].

Confined placental mosaicism and pregnancy outcome: a distinction needs to be made between types 2 and 3.

Objective: To study the influence of types 2 and 3 confined placental mosaicism (CPM) on pregnancy outcome.

Method: From 13 809 chorionic villus samplings (CVSs), karyotype after long-term cultured villi (LTC-villi) was systematically performed. Next, in case of suspicion of CPM, karyotype after short-term cultured villi (STC-villi) was established to define type 2 CPM (chromosomal abnormality limited to the mesenchymal core) or type 3 CPM (chromosomal abnormality found both in the cytotrophoblast and the mesenchymal core).

Characterization of a de novo balanced translocation t(9;18)(p23;q12.2) in a patient with oculoauriculovertebral spectrum.

We report a patient presenting with oculoauriculovertebral spectrum and a de novo balanced reciprocal translocation t(9;18)(p23;q12.2). Physical mapping of the translocation breakpoints by fluorescent in situ hybridization showed that the breakpoints are located in two regions encompassing gene deserts.

[Maze-like vascular anomaly in partial mole. Interest for the pathological diagnosis of partial mole on chorionic villous sampling].

A case of maze-like angiomatoid anomaly in villi obtained by chorionic villous sampling (CVS) is described. This feature is pathognomonic of partial mole (triploid syndrome) and it was later confirmed by chromosomal analysis. Maze-like angiomatoid anomaly was previously described on specimen submitted after spontaneous or induced abortions, but it was never reported on CVS.

[Advantages and limitations of chorionic villous sampling].

Chorionic villous sampling (CVS) has been available for more than twenty years. Together with amniocentesis, it helps the cytogenetician to determine the fetal karyotype for prenatal diagnosis. The choice between these two methods depends on the team and the indication.

Nutritional and genetic determinants of vitamin B and homocysteine metabolisms in neural tube defects: a multicenter case-control study.

Neural tube defects (NTDs) are severe congenital malformations due to failure of neural tube formation in early pregnancy. The proof that folic acid prevents NTDs raises the question of whether other parts of homocysteine (Hcy) metabolism may affect rates of NTDs. This French case-control study covered: 77 women aged 17-42 years sampled prior to elective abortion for a severe NTDs (cases) and 61 women aged 20-43 years with a normal pregnancy.

[Smith-Lemli-Opitz syndrome].

SLO syndrome is an autosomal recessive condition with multiple malformations. This syndrome is ascribed to deficiency of 7 dehydrocholesterol reductase, an enzyme in the cholesterol biosynthetic pathway. The characteristics of this syndrome are facial anomalies, syndactyly of the second and third toe, postaxial polydactyly and genital anomalies with sexual ambiguity.

X-linked dominant chondrodysplasia with platyspondyly, distinctive brachydactyly, hydrocephaly, and microphthalmia.

We describe a family with an X-linked dominant chondrodysplasia. Four males and six females were affected through four generations. Identification of skeletal abnormalities and hydrocephaly during the pregnancy of three male fetuses led to termination of the pregnancies.

Monozygotic twins concordant for blood karyotype, but phenotypically discordant: a case of "mosaic chimerism".

We report on 23 years old discordant monozygotic (MZ) twins, one with minor anomalies and mental delay, the other one being normal. Both had 46,XX,dup(11)(p12p15)/46,XX mosaicism in blood, with a similar proportion of abnormal cells (respectively, 16% and 17%). However, interphase fluorescence in situ hybridization (FISH) analysis performed on buccal smear and urinary sediment using specific probes located at the duplicated region showed that mosaicism was only present in the abnormal twin, with 68% abnormal cells.

Prenatal diagnosis and management of sex chromosome aneuploidy: a report on 98 cases.

Objectives: To analyse the management of pregnancy after prenatal diagnosis of sex chromosome aneuploidy (SCA) and the factors influencing genetic counselling and parental decision.

Methods: Between 1991 and 2001, 73 non-mosaic fetal SCA were diagnosed in our centre and 25 were referred to us from outside institutions. The same geneticist carried out genetic counselling.

Craniofacial dysmorphology and three-dimensional ultrasound: a prospective study on practicability for prenatal diagnosis.

Objective: The aim of this study is to compare two-dimensional and three-dimensional ultrasound for the visualization and diagnosis of craniofacial dysmorphism.

Methods: In this prospective study, we performed three-dimensional (3D) ultrasound following good-quality two-dimensional (2D) ultrasound in an at-risk population. Findings from 2D and 3D examination were noted.

Donnai-Barrow syndrome: four additional patients.

In 1993, Donnai and Barrow reported a new syndrome in two sets of sibs and in an unrelated child, including diaphragmatic hernia, exomphalos, absent corpus callosum, hypertelorism, myopia, and sensorineural deafness. Since then, only four similar patients have been documented. We describe four additional patients, including two sibling pairs from healthy parents.

Feasibility, accuracy and safety of chorionic villus sampling: a report of 10741 cases.

Objectives: To evaluate the feasibility, accuracy and safety of chorionic villus sampling (CVS).

Methods: Ten thousand seven hundred and forty one singleton pregnancies at risk of chromosome abnormalities (96.3%) and gene disorders (2.