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Mutations in more than 150 genes are responsible for inherited hearing loss, with thousands of different, severe causal alleles that vary among populations. The Israeli Jewish population includes communities of diverse geographic origins, revealing a wide range of deafness-associated variants and enabling clinical characterization of the associated phenotypes. Our goal was to identify the genetic causes of inherited hearing loss in this population, and to determine relationships among genotype, phenotype, and ethnicity. Genomic DNA samples from informative relatives of 88 multiplex families, all of self-identified Jewish ancestry, with either non-syndromic or syndromic hearing loss, were sequenced for known and candidate deafness genes using the HEar-Seq gene panel. The genetic causes of hearing loss were identified for 60% of the families. One gene was encountered for the first time in human hearing loss: ATOH1 (Atonal), a basic helix-loop-helix transcription factor responsible for autosomal dominant progressive hearing loss in a five-generation family. Our results demonstrate that genomic sequencing with a gene panel dedicated to hearing loss is effective for genetic diagnoses in a diverse population. Comprehensive sequencing enables well-informed genetic counseling and clinical management by medical geneticists, otolaryngologists, audiologists, and speech therapists and can be integrated into newborn screening for deafness.

Mutations in more than 150 genes are responsible for inherited hearing loss, with thousands of different, severe causal alleles that vary among populations. The Israeli Jewish population includes communities of diverse geographic origins, revealing a wide range of deafness-associated variants and enabling clinical characterization of the associated phenotypes. Our goal was to identify the genetic causes of inherited hearing loss in this population, and to determine relationships among genotype, phenotype, and ethnicity. Genomic DNA samples from informative relatives of 88 multiplex families, all of self-identified Jewish ancestry, with either non-syndromic or syndromic hearing loss, were sequenced for known and candidate deafness genes using the HEar-Seq gene panel. The genetic causes of hearing loss were identified for 60% of the families. One gene was encountered for the first time in human hearing loss:ATOH1(Atonal), a basic helix-loop-helix transcription factor responsible for autosomal dominant progressive hearing loss in a five-generation family. Our results demonstrate that genomic sequencing with a gene panel dedicated to hearing loss is effective for genetic diagnoses in a diverse population. Comprehensive sequencing enables well-informed genetic counseling and clinical management by medical geneticists, otolaryngologists, audiologists, and speech therapists and can be integrated into newborn screening for deafness.

ObjectiveTo examine the risk for abnormal chromosomal microarray analysis (CMA) results among fetuses with an apparently isolated pelvic kidney.MethodsData from all CMA analyses performed due to an isolated pelvic kidney reported to the Israeli Ministry of Health between January 2013 and September 2016 were retrospectively obtained. Risk estimation was performed comparing the rate of abnormal observed CMA findings to the general population risk, based on a systematic review encompassing 9272 cases and on local data of 5541 cases.ResultsOf 120 pregnancies with an isolated pelvic kidney, two gain-of-copy number variants suggesting microduplication syndromes were demonstrated (1.67%). In addition, three variants of unknown significance were detected (2.5%).ConclusionThe risk for clinically significant CMA findings among pregnancies with an isolated single pelvic kidney was not significantly different compared to both control populations. The results of our study question the practice of routine CMA analysis in fetuses with an isolated pelvic kidney.

Pigmentary retinal dystrophy and macular dystrophy have been previously reported in Heimler syndrome due to mutations in PEX1. Here we reported the ocular manifestations in Heimler syndrome due to mutations in PEX6.Medical records were reviewed to identify patient demographics, ophthalmic and systemic findings, and results of diagnostic testing including whole genome sequencing.Patient 1 is 12-year-old boy with a novel mutation c.275TG (p.Val92Gly) and known mutation c.1802GA (p.Arg601Gln) in PEX6. Patient 2 is a 7-year-old girl with the same known c.1802GA (p.Arg601Gln) mutation and another novel missense mutation c.296GT (p.Arg99Leu). Both patients exhibited a pigmentary retinopathy. Visual acuity in patient 1 was 20/80 and 20/25 following treatment of intraretinal cystoid spaces with carbonic anhydrase inhibitors, while patient 2 had visual acuity of 20/20 in both eyes without intraretinal cysts. Fundus autofluorescence showed a multitude of hyperfluorescent deposits in the paramacular area of both eyes. OCTs revealed significant depletion of photoreceptors in both patients and macular intraretinal cystoid spaces in one patient. Full field electroretinograms showed normal or abnormal photopic but normal scotopic responses. Multifocal electroretinograms were abnormal.Heimler syndrome due to biallelic PEX6 mutations demonstrates a macular dystrophy with characteristic fundus autofluorescence and may be complicated by intraretinal cystoid spaces.

To evaluate the impact of genetic counseling (GC) during the third trimester by analyzing changes in pregnancy management and the correlation with postnatal findings. This was a retrospective study. Pregnancy course and neonatal follow-up were analyzed according to the reason for referral and implementation of recommendations. The records of neonates born to 181 women were retrieved. Fifty-two women (group 1—29%) qualified for pregnancy termination under Israeli guidelines and laws, and 129 (group 2—71%) were not at the time they were referred. By another division: 104 women (group 3—57%) followed the physician’s diagnostic recommendations completely after counseling including amniocentesis, fetal MRI, targeted ultrasound scans, fetal echocardiography. Seventy-seven declined amniocentesis (group 4—43%). Additional abnormalities were detected postpartum in all groups without statistically difference: 3/52 (10%) in group 1, 9/129 (7%) in group 2, 6/104 (6%) in group 3, and 6/77 (8%) in group 4). GC in the third trimester of pregnancy provided the couple with a sharper more focused picture and assisted them to perceive the significance of new, significant fetal findings which attest to the value of the GC.

Metaphyseal anadysplasia (MANDP) is a rare autosomal recessive form of skeletal dysplasia characterized by normal length at birth and transitory bowing of the legs. Although several families with MANDP have been reported, homozygous mutations in the matrix metalloproteinase type 9 (MMP9) gene have been described in only one consanguineous family, and thus the pre and postnatal phenotypic spectrum is still obscure. A clinically similar but more severe type is caused by autosomal-dominant inheritance and is caused by mutations in matrix metalloproteinase type 13 gene (MMP13). Here, we report the prenatal and early postnatal course of two affected sib fetuses with early sonographic evidence of long bone shortening and postnatally no metaphyseal changes. Whole-exome sequencing revealed homozygous mutation in MMP9 in both fetuses suggesting a diagnosis of MANDP. We propose that MANDP should be considered in pregnancies with early prenatal shortening of the long bones without associated finding of lethal skeletal dysplasias. In addition, the finding of homozygous mutation in non-consanguineous parents of Jewish-Caucasus ancestry may suggest unawareness of such relation or the occurrence of a founder mutation in this gene.

Objectives An association between isolated, increased nuchal translucency thickness and pathogenic chromosomal microarray analysis (CMA) has been reported. A recent meta-analysis reported that most studies used a 3.5 mm cut-off value. Considering nuchal translucency distribution and the commonly accepted 5% false positive rate in maternal serum screening, nuchal translucency cut-off levels should be reconsidered. This study evaluated the unique contribution of CMA to the investigation of foetuses with mildly increased nuchal translucency (NT) thickness of 3.0-3.4 mm. Methods This was a retrospective, multicenter study. A single laboratory performed all genetic analyses. Comparative Genomic Hybridization Microarray analysis or Single Nucleotide Polymorphism Array technology was used for CMA. NT was divided into three groups (≤2.9; 3.0-3.4; ≥3.5 mm) and the results were compared, focusing on pregnancies with NT as the only medical indication for CMA at the time of the invasive procedure. If combined first trimester screening (NT and biochemistry) indicated increased risk for common aneuploidies, the case was excluded. Results CMA results were recorded in 1,588 pregnancies, of which 770 foetuses had NT as a normal or an isolated abnormal finding. Of these, 462 had NT ≤2.9 mm, 170 had NT 3.0-3.4 mm and 138 had NT ≥3.5 mm. Pathogenic copy number variations were found in 1.7%, 7.1%, and 13.0%, respectively. Conclusions The results suggest that CMA should be part of the investigation in foetuses with isolated, mildly increased NT (3.0-3.4 mm).

Introduction Delayed villous maturation and accelerated villous maturation diagnosed in histologic sections are morphologic manifestations of pathophysiological conditions. The inter-observer agreement among pathologists in assessing these conditions is moderate at best. We investigated whether automated image analysis of placental villi and syncytial knots could improve standardization in diagnosing these conditions. Methods Placentas of antepartum fetal death at or near term were diagnosed as normal, delayed or accelerated villous maturation. Histologic sections of 5 cases per group were photographed at ×10 magnification. Automated image analysis of villi and syncytial knots was performed, using ImageJ public domain software. Analysis of hundreds of histologic images was carried out within minutes on a personal computer, using macro commands. Results Compared to normal placentas, villi from delayed maturation were larger and fewer, with fewer and smaller syncytial knots. Villi from accelerated maturation were smaller. The data were further analyzed according to horizontal placental zones and groups of villous size. Discussion Normal placentas can be discriminated from placentas of delayed or accelerated villous maturation using automated image analysis. Automated image analysis of villi and syncytial knots is not equivalent to interpretation by the human eye. Each method has advantages and disadvantages in assessing the 2-dimensional histologic sections representing the complex, 3-dimensional villous tree. Image analysis of placentas provides quantitative data that might help in standardizing and grading of placentas for diagnostic and research purposes.

To assess the mid-trimester triple test biomarkers among women diagnosed with vasa previa (VP).The study included 43 singleton pregnancies diagnosed with vasa previa between the years 1988 and 2011. The mid-gestation screening test for Down syndrome was calculated from the combination of triple serum markers and maternal age, and expressed as a multiple of the gestation specific normal mean (MoM). Reference MoM values were calculated from the local population. The levels of mid-gestation maternal serum alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) of patients with VP were compared with control reference group.The mean hCG and αFP levels of women diagnosed with VP was significantly higher compared to control reference group (1.42 versus 0.99 MoM; p .002 and 1.24 versus1.01 MoM; p .001, respectively). In contrast, there was no significant difference in uEOur findings suggest that increased mid-gestation hCG and AFP were found among pregnancies complicated with VP. Clinicians should consider targeted scanning of pregnant women with risk factors for VP, including unexplained high maternal levels of hCG and αFP of the triple test, while conducting mid-gestation anomaly scan.

Objective To evaluate the association between aberrant right subclavian artery (ARSA), with or without additional risk factors for aneuploidy or ultrasound abnormality, and results of chromosomal microarray analysis (CMA). Methods This was a multicenter study of fetuses diagnosed with ARSA that underwent genetic analysis by CMA, all samples being analyzed in the same laboratory. Clinical investigation included nuchal translucency measurement, first- and second-trimester maternal serum screening, early and late second-trimester fetal anatomy scans and fetal echocardiography. Comparative genomic hybridization microarray analysis or single-nucleotide polymorphism array technology was used for CMA of DNA samples obtained from amniotic fluid. Results CMA results were available for 63 fetuses with ARSA. In 36 fetuses, ARSA was an isolated finding, and no pathogenic variant was found. Additional ultrasound findings and/or risk factors for aneuploidy were present in 27 fetuses, five of which had pathogenic CMA results. Of these five, trisomy 21 was detected in a fetus with echogenic intracardiac focus (EIF), 22q11 deletion was detected in a fetus with EIF and an increased risk of trisomy 21 of 1:230 from maternal serum screening, 22q11 duplication was detected in a fetus with hypoplastic right kidney and choroid plexus cyst and 22q11 deletion was detected in a fetus with right aortic arch and clubfoot. The fifth fetus had increased nuchal translucency thickness (4 mm) and a ventricular septal defect, and CMA identified both 22q11 deletion and 1q21 duplication. Conclusions In fetuses with isolated ARSA, an invasive procedure for CMA is not indicated. However, CMA is recommended when additional ultrasound abnormalities or risk factors for aneuploidy are observed. The chromosomal findings in four of the five cases with an abnormal CMA result in our study would not have been detected by standard fetal chromosomal testing. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Introduction Congenital contractural arachnodactyly (CCA) is a rare connective tissue disorder, associated with heterozygous mutations in the FBN2 gene. The objective of this study was to evaluate the prevalence of an intragenic deletion encompassing exons 1–8 of FBN2 gene in Israeli population. Materials and methods A search for intragenic FBN2 microdeletions was performed in two databases of chromosomal microarray analysis (CMA) – genetic laboratory of a tertiary medical center (the primary cohort) and one of the largest Israeli health maintenance organizations (replication cohort). Results Overall, 52,879 microarray tests were searched for FBN2 microdeletions. The primary cohort constituted of 18,301 CMA tests, among which 33 intragenic FBN2 microdeletions in unrelated individuals were found (0.18%). Prenatal prevalence of this variant was 0.23% (28/12,604), and specifically in low risk pregnancies - 0.29% (22/7464). Of the 28 cases with known parental origin, 27 (96.4%) were of full or partial Ashkenazi Jewish ethnic background. The approximate allele incidence in the Ashkenazi Jewish origin was 0.4% (18/4961). Combined with the 34,578 CMA tests in the replication cohort, the overall frequency of FBN2 microdeletions was 0.24% (125/52,879). None of the pre- or postnatal cases had any clinical manifestations of CCA. Discussion Intragenic FBN2 microdeletions are found in one of every 420 CMA analyses in Israeli population, and in particular one of every 340 low-risk pregnancies. Due to high allele incidence in Ashkenazi Jewish population (1:275), we suggest that FBN2 gene deletion detected by CMA among Ashkenazi Jews should be interpreted as benign copy number variant.

The purpose of the present study was to examine screening marker levels in Down syndrome (DS) pregnancies with and without cardiac defects and in euploid pregnancies. Retrospective series in two centers with one or more markers—ultrasound nuchal translucency (NT), first trimester maternal serum pregnancy associated plasma protein (PAPP-A), free-β human chorionic gonadotrophin (free β-hCG), and second trimester serum α-fetoprotein (AFP), unconjugated estriol (uE3), hCG, and free-β hCG. Levels were expressed as multiples of the gestation-specific median (MoM). Differences were assessed by the Wilcoxon rank sum test and 95 % confidence intervals. There were 318 DS pregnancies including 53 (17 %) with cardiac defects. Median NT was higher in cardiac defects (1.82 compared with 1.62 MoM), but not statistically significant (P = 0.17). Median free β-hCG was significantly highly reduced in the first trimester (1.14 and 2.17 MoM; P < 0.005) and similarly but nonsignificantly in the second trimester (1.59 and 2.32 MoM; P = 0.14). PAPP-A was reduced and AFP increased nonsignificantly with no material differences for uE3 and hCG. The results on NT and free β-hCG were consistent with a series of 62 euploid pregnancies with cardiac defects screened in one of the centers. The distribution of some markers differs in DS pregnancies with cardiac defects. Depending on the screening protocol, this may affect the phenotype of DS births.

Spinocerebellar ataxia type 3 is an autosomal dominant ataxia with various phenotypes affecting Jews of Yemenite origin in Israel. Clinical and family pedigrees data of 125 Yemenite Jewish patients were collected in our clinic. All examined patients underwent a detailed neurological and bedside vestibular examination. Cytosine–adenine–guanine repeats size in the Ataxin-3 gene was measured, and patients with expanded cytosine–adenine–guanine repeats >44 were diagnosed genetically as having spinocerebellar ataxia type 3. We estimated a disease prevalence rate of about 29/100,000 in Jew of Yemenite descendents living in Israel. We were able to group patients into 17 families. Mean age of onset was 44 years. 74 % of our population expressed neurological signs compatible with sub-phenotype III, i.e., ataxia and polyneuropathy. Vestibulo-ocular reflex deficit detected on bedside examination was found in 90 % of the patients. The mean number of cytosine–adenine–guanine repeats in the Ataxin-3 gene of the diseased allele was 67 (range 55–76). Age of onset was inversely correlated with the number of cytosine–adenine–guanine repeats (r = −0.7) and was significantly earlier among male patients. Though the mean number of cytosine–adenine–guanine repeats was not larger in the offspring, their age of onset was significantly earlier than that of their parents. In addition, paternal offspring expressed the disease significantly earlier than maternal offspring. Signs and stages of disease seem to progress slower during the first 10–15 years of the disease and faster afterward. A high disease prevalence rate in our Yemenite Jewish subpopulation is similar to that found in other isolated populations in other countries. Vestibulo-ocular reflex deficit detected on bedside examination should be added as part of the phenotype of Yemenite Jewish patients. Our clinical and genetic findings are in partial agreement with other spinocerebellar ataxia type 3 population studies and are relevant to patient management and the design of further studies.

Agenesis of the corpus callosum is currently diagnosed prenatally with ultrasound and MRI. While the diagnostic aspects of callosal defects are widely addressed, anatomo-histological data from fetal autopsies are sparse. Callosal defects were present in 50 fetal autopsies. Four distinct groups of complete, partial, hypoplastic, and mixed defects were determined by the gross and histologic details of the corpus callosum. These details helped to rule out other midline defects such as holoprosencephaly. Additional autopsy findings enabled specific diagnoses and suggested etiopathogeneses. Hypoplastic and mixed defects were associated with more abnormalities of the cerebral hemispheres and internal organs. The four groups did not differ according to gender, external dysmorphism, or cerebellar and brainstem anomalies. Defects were classified as syndromic (68 %), encephaloclastic (8 %), undetermined (14 %), or isolated (10 %) based on the autopsy findings. Isolated agenesis of the corpus callosum was diagnosed in only 10 % of the cases in this series, compared to higher numbers diagnosed by prenatal ultrasonography and MRI. Therefore, the autopsy, through its detailed, careful evaluation of external, as well as gross and histological internal features, can elucidate the etiopathogenesis of agenesis of the corpus callosum and suggest specific diagnoses which cannot be ascertained by prenatal imaging.

The use of maternal serum alpha fetoprotein (MSAFP) levels as a predictor of pregnancy complications (PC) is well established. We hypothesized that the ratio between the MSAFP/AFAFP levels (RATIO) will more accurately predict PC than MSAFP levels alone. Women who had a MSAFP test followed by amniocentesis were divided into two groups: those who had PC comprised the study group and those who had an uneventful pregnancy served as the control group. Data regarding pregnancy and delivery course were collected. The RATIO between the study and the control groups was compared. 166 women were included in the study, of which 24 had PC. A significant correlation was found between the RATIO and intrauterine growth restriction (IUGR) and week of delivery. Six pregnancies had elevated MSAFP levels; two with RATIO below 2 had uneventful pregnancies. Among the other four pregnancies with RATIO above two, one had IUGR and the other, placental abruption. Our data suggest that the RATIO might serve as a predictor of IUGR and week of delivery. Although the number of patients in the current study was relatively small, the novelty of the proposed simple marker implies that a larger scale study is warranted. Such studies may confirm this finding and a possible advantage of using this RATIO instead of or in addition to MSAFP values for better prediction of pregnancies at risk for PC.

The objective of this study is to examine the frequency of abnormal Chromosomal Microarray (CMA) analyses among fetuses with isolated non-visualization of fetal gallbladder.Data from CMA analyses performed due to isolated non-visualization of fetal gallbladder between January 2013 and September 2016 were retrospectively acquired from a computerized database of the Israeli Ministry of Health. The results were compared with the rate for clinically significant CMA findings in general population, based on a large cohort of 5541 pregnancies undergoing CMA due to maternal request, and a systematic review of 9272 cases with normal ultrasound.Of 45 pregnancies with isolated non-visualization of fetal gallbladder, CMA testing yielded one (2.22%) gain-of-copy-number variant at 16p11.2, categorized as "pathogenic". In addition, one finding of unknown significance was demonstrated. The risk for clinically meaningful CMA findings among pregnancies with isolated absent gallbladder was not significantly increased compared to control population.To the best of our knowledge, this study is the first report describing the rate of pathogenic CMA results in fetuses with isolated non-visualization of fetal gallbladder. The results, in conjunction with previous studies, show that the risk for abnormal CMA results in pregnancies diagnosed with non-visualized gallbladder is not significantly different from pregnancies with normal ultrasound.

The purpose of this study was to analyse the association between free beta hCG (fβhCG) increased levels and pregnancy complications (PC), foetal growth restriction (FGR) and preeclampsia (PE). This connection was evaluated in two stages (i) investigating the association between those PC with first trimester fβhCG and second trimester intact hCG (ihCG), and (ii) studying the association between these two analytes in the same pregnancy. This was a retrospective study in two settings: medical centre that provided data on fβhCG and ihCG levels in pregnancies with FGR and PE, and central laboratory that provided fβhCG and ihCG levels that were compared in the same pregnancy. No association was found between those PC and the hCG analytes, except for elevated ihCG levels and FGR. Elevated fβhCG (3.00 MoM) was found in 570/16,849 (3.4%) women. However, only 14% of whom had elevated second trimester ihCG. A positive correlation was found between the magnitude of first trimester fβhCG levels and the percentage of women who had elevated second trimester ihCG. This association was determined by the magnitude of the elevation of fβhCG levels. Impact statement What is already known on this subject: The two analytes, first trimester fβhCG and second trimester ihCG, are independently produced and parameters of the biochemical screening during pregnancy. What the results of this study add: Referring to 3.00 MoM as cut-off levels, most pregnancies with elevated levels of first trimester fβhCG will have normal ihCG second trimester levels. What the implications are of these findings for clinical practice and/or further research: The risk of developing pregnancy complications, FGR and PE should be associated with second trimester ihCG levels. About 3.5% of women had high fβhCG levels during the first trimester. However, only 14% also had increased ihCG levels, defined as 3.00 MoM; additional studies are needed to explore the association between increased first trimester fβhCG levels and the risk of developing pregnancy complications, independent of ihCG levels in the second trimester.

To evaluate the yield of work-up in intrauterine growth restriction (IUGR) pregnancies and their outcomes.Retrospective data regarding prenatal work-up (serology, genetic testing and imaging), and neonatal outcomes of 198 IUGR pregnancies (estimated fetal weight10th percentile) were analyzed.IUGR was isolated in 72 cases. Work-up performed in 158 (80%) cases was positive in 4 (2.5%). No abnormalities were detected in prenatal genetic testing. Echocardiogram performed in 27 cases was abnormal in 3 (11.1%). Serological testing performed in 150 pregnancies (75.8%) detected 1 case (0.7%) of cytomegalovirus (CMV) infection. Thirteen neonates (6.5%) were diagnosed with significant health problems. A positive work-up and significant postnatal health problems were not correlated with IUGR severity, symmetry or additional concurrent findings.The yield of IUGR work-up is not clear and is probably highest for fetal echocardiography. The rate of significant adverse outcomes after birth is increased in IUGR pregnancies.

This study assessed the correlation between the magnitude of the elevation in maternal serum human chorionic gonadotropin (MShCG) levels and pregnancy complications. Among 80,716 screened pregnancies, 120 with moderately elevated MShCG (3.00-5.99 MoM) were compared to 84 with extremely elevated MShCG6.00 MoM. A control series of 120 women with normal MShCG (3.00 MoM) were matched. Rates of intrauterine growth restriction, preterm labour, antepartum foetal death (APFD), pre-eclampsia, and placental abruption were analysed. We found that the study group had more adverse outcomes than the control group (73/204 [36%] vs. 18/120 [15%]; p .0001). The rate was higher in the extremely elevated group than in the moderately elevated group (43/84 [51%] vs. 30/120 [25%]; p .0001). All 12 cases of APFD (14%) occurred among the extremely elevated series. In conclusion, adverse pregnancy outcomes are more common in women with extremely elevated MShCG. The patients should receive counselling regarding this trend and undergo close pregnancy monitoring. Impact statement • What is already known on this subject?In addition to its contribution to Down syndrome (DS) screening, maternal serum human chorionic gonadotropin (MShCG) levels are a marker for pregnancy complications such as intrauterine growth restriction (IUGR), preterm labour (PTL), antepartum fatal death (APFD), pre-eclampsia (PE), placental abruption (PA) and fetal malformations with or without chromosomal aberrations. • What the results of this study add? We found that in the presence of elevated MShCG levels, the incidence of IUGR and PTL increased. PE increased clinically, but statistical significance was seen only when MShCG was extremely elevated (≥ 6.00 MoM). APFD and PA were associated with very high MShCG levels only. • What the implications are of these findings for clinical practice and/or further research? Women with high MShCG levels should be counselled. In case of very high levels (≥ 6.00 MoM), the risk of APFD and PA should be discussed. The pregnancy should be monitored for IUGR, PTL and PE. In view of the limited number of enrolled patients with very high levels of MShCG, the experience of other institutions is needed to corroborate these findings.

PurposeTo compare the frequency of copy-number variants (CNVs) of variable penetrance in low-risk and high-risk prenatal samples and postnatal samples.MethodsTwo cohorts were categorized according to chromosomal microarray analysis (CMA) indication: group I, low-risk prenatal-women with uneventful pregnancy (control group); group II, high-risk prenatal-women whose fetuses had congenital malformations; and group III, postnatal-individuals with unexplained developmental delay/intellectual disability, autism spectrum disorders, or multiple congenital anomalies. CNVs were categorized based on clinical penetrance: (i) high (40%), (ii) moderate (10-40%), and (iii) low (10%).ResultsFrom 2013 to 2016, 21,594 CMAs were performed. The frequency of high-penetrance CNVs was 0.1% (21/15,215) in group I, 0.9% (26/2,791) in group II, and 2.6% (92/3,588) in group III. Moderate-penetrance CNV frequency was 0.3% (47/15,215), 0.6% (19/2,791), and 1.2% (46/3,588), respectively. These differences were statistically significant. The frequency of low-penetrance CNVs was not significantly different among groups: 0.6% (85/15,215), 0.9% (25/2,791), and 1.0% (35/3,588), respectively.ConclusionHigh-penetrance CNVs might be a major factor in the overall heritability of developmental, intellectual, and structural anomalies. Low-penetrance CNV alone does not seem to contribute to these anomalies. These data may assist pre- and posttest CMA counseling.

Objective To report and discuss the observation of three fragments on polymerase chain reaction (PCR) in routine carrier screening for fragile X. Methods From 2005 through 2010, 34,500 women underwent prenatal screening for fragile X. PCR was carried out to amplify the repeat segment. The resulting fragments were scanned by a genetic analyser. Results Three PCR peaks representing three different-sized fragments were found in 25 of the 34,500 women (1:1380 or 0.072%). Karyotype analysis was performed in 16 subjects. Full triple X was found in three women, while two had triple X mosaicism. Of the 16 karyotyped women, five (31%) had a finding of XXX (full or mosaic). Conclusions Triple X (full or mosaic) is the most frequently encountered mechanism responsible for three peaks on fragile X PCR testing.

Objective Individuals with chromosomal aneuploidies tend to develop malignancies. Telomerase is an enzyme complex that lengthens telomeres and has enhanced expression in numerous malignancies; one of its components is encoded by the TERC gene. In this study, we evaluated the TERC gene copy number in amniocytes from fetuses with aneuploidy, other than trisomy-21. Methods In this prospective, basic research study, fluorescence in situ hybridization (FISH) for the TERC gene (3q26) was applied to amniocytes retrieved from 14 fetuses with various aneuploidies and from a control group of 6 fetuses with a normal karyotype, to determine the TERC gene copy number. Results The percentage of cells with more than two copies of the TERC gene was lowest in the control group (x3 = 1.2 ± 0.4%; x4 = 0 ± 0%), higher in the sex chromosome aneuploidies (x3 = 4 ± 3%; x4 = 0.7 ± 0.95%) and even higher in trisomy 18 (x3 = 10.6 ± 2.3; x4 = 4.6 ± 1.8). The differences were statistically significant (P Conclusion The TERC gene copy number is increased in aneuploid amniocytes, which demonstrates their genetic instability and is presumably related to their tendency to develop malignancies.

Fetal liver calcifications are occasionally found in fetal autopsies. However, the incidence, associated findings, clinical significance, and presumed pathogenesis of fetal liver calcifications are not well documented. This study analyzed the characteristics and significance of fetal liver calcifications found on fetal autopsies. Cases of fetal liver calcifications were collected from a fetal autopsy database. Their clinical and pathological characteristics were analyzed in comparison to the remaining cases in the database. Thirty-five cases (4.2%) of fetal liver calcifications were found among 827 consecutive fetal autopsies that had been performed in our hospital during the 16-year period from January 1, 1994 through December 31, 2009. Twenty-nine cases had nodular calcifications, predominantly subcapsular. Calcification in portal spaces and porta hepatis were present in six cases. Twenty cases were missed abortions and intrauterine fetal death. Missed abortion at or earlier than 23 weeks had significantly more subcutaneous edema and other evidence of circulatory abnormalities. Calcifications in older fetuses (>23 weeks) were located more commonly in portal spaces and in other organs. Fetal liver calcification is an incidental finding during autopsies. The significance of fetal liver calcifications has to be assessed in combination with other clinical and pathological parameters, including location and number of the lesions, signs of circulatory compromise, and abnormalities of placenta, umbilical cord, and fetal malformations. Fetal liver calcifications are commonly associated with conditions related to impaired circulation, including umbilical cord abnormalities and subcutaneous edema. We suggest that fetal liver calcifications might attest to circulatory compromise preceding death, especially if subcutaneous edema is present and even when no other abnormal findings are seen.

Background Current risk calculations for trisomy 21, which are based on multiples of median (MoM), do not take into account possible differences between euploid and trisomy 21 pregnancies that may develop with gestational age. In order to optimize the predictive value of screening tests, we calculated the ratio between maternal serum concentration of alpha-fetoprotein (AFP) and that of human chorionic gonadotropin (hCG) in euploid and in trisomy 21 pregnancies. Methods The medians of the concentration ratios, [AFP]/[hCG] at 16–21 weeks of gestation, were plotted as a function of gestational age for 307 cases of trisomy 21 and were compared with the medians of 30 549 normal karyotype cases. Results [AFP]/[hCG] ratio medians were independent of body weight and maternal age. There was a significant difference in the [AFP]/[hCG] ratio when comparing trisomy 21 and euploid pregnancies at each week. This difference became greater with advancing gestational age (P < 0.01). Conclusion There is a significant difference in ratios of [AFP]/[hCG] between euploid and trisomy 21 pregnancies, which may be used to improve detection rates of Down syndrome screening. Copyright © 2009 John Wiley & Sons, Ltd.

Trisomy 21 is the most common chromosomal abnormality among persons with intellectual disability, with a live birth rate of 1 in 800-1,000. As such, this abnormality may serve as a model for human disorders that result from supernumerary copies of a genomic region. Down syndrome carries an increased risk of developing acute leukemia and other malignancies. Telomeres of tumor cells nuclei tend to form aggregates (TA). This study evaluated TA formation in amniocytes from trisomy 21 pregnancies, compared with amniocytes from normal euploid pregnancies. A commercially available peptide nucleic acid telomere kit was used to evaluate TA formation, using two-dimensional fluorescence microscopy. Significantly higher frequencies of TA were found in trisomy 21 amniocytes than in amniocytes from normal pregnancies. The TAs found in trisomy 21 amniocytes apparently represent an additional parameter that reflects the high genetic instability of this syndrome and its recognized predisposition to develop leukemia and other malignancies.

Telomeres are specific repetitive DNA sequences that cap and stabilize the ends of chromosomes. Functional telomeres are essential for the normal segregation and maintenance of chromosomes during mitotic and meiotic division. Pre-eclampsia, a pregnancy-specific syndrome of increased blood pressure accompanied by proteinuria, is often associated with growth deficiency in the fetus. Oxidative stress is a major component in the pathophysiology of pre-eclampsia. In contrast to the nonoverlapping nature of telomeres in normal nuclei, telomeres of tumor nuclei tend to form aggregates (TAs) in various numbers and sizes. The formation of TAs represents a stress-related process and is independent of telomere length and telomerase activity. The aim of this study was to evaluate TA formation in paraffin-embedded placentas from pregnancies complicated with pre-eclampsia (study group), compared with placentas from normal pregnancies (control group). There were significantly more TAs in the study group (mean, 8.00 TAs per case) than in the control group (mean, 2.36 TAs per case) (P < 0.01). Pre-eclampsia-related stress may accelerate apoptosis and cell death and lead to placental dysfunction. TAs formation, which has been linked to stress and tumorgenesis is increased in placentas of pre-eclamptic patients.

Objective To evaluate the safety of oocyte activation by calcium ionophore in cases of failed fertilization after intracytoplasmic sperm injection (ICSI) procedure with respect to birth defects. Design A retrospective cohort of pregnancies achieved by oocyte activation with calcium ionophore after ICSI (ICSI-Ca) and routine ICSI between the years 2006 and 2014. Setting Not applicable. Patient(s) The cohort included a total of 793 pregnancies: 66 (8%) were lost to follow up and 49 (6%) were ongoing pregnancies at the time of data collection. Out of the 678 available cases for analysis, 595 treatments were ICSI alone (88%) and 83 were ICSI-Ca (12%). Intervention(s) None. Main Outcome Measure(s) Pregnancy and neonatal outcomes including birth defects were compared. Result(s) On the basis of a cohort of 595 ICSI pregnancies and 83 ICSI-Ca pregnancies, we found no difference in birth defects rate for singletons or for twins. Additionally, no significant difference was found between defect type (chromosomal aberration or structural malformations) and malformation type (heart, urogenital, and limb), between the ICSI and ICSI-Ca groups. Moreover, no significant differences were found regarding birth weight, gestational week at time of delivery, and fetal gender for singleton or twin pregnancies. Conclusion(s) Ca ionophore oocyte activation should be considered as a legitimate option for cases of failed or low fertilization by ICSI.

Objective Diabetes during pregnancy causes an intrauterine environment that influences lifetime sickness of the mother and the fetus. There is a correlation between diabetes and telomere shortening; however, very little is known about telomere homeostasis in the placenta. We aimed to study the telomerase complex in placentas and in cord blood leukocytes from patients with poorly controlled diabetes. Methods Biopsies from 16 third-trimester placentas and cord blood samples from pregnancies complicated with uncontrolled diabetes and from 16 gestational age-matched controls from uncomplicated pregnancies were examined. The expression of hTERT (human telomerase reverse transcriptase) was evaluated by immunohistochemistry and by RT-RCR. TERC gene copy number and telomere capture were evaluated by FISH. Results Telomerase expression was significantly lower in the diabetic placentas, both the protein (17.8 ± 2.8% cellular staining vs. 37 ± 5.32%, P = 0.012) and the mRNA levels (0.42 ± 0.03 folds, P = 0.022). Lower expression of TERC gene copy number were shown in the diabetic placentas compared to the healthy controls (1.7 ± 0.8% vs. 3.7 ± 1.6%, P = 0.035). We also detected higher percentage of cells with telomere capture among the diabetic trophoblasts compared to the healthy controls (19.8 ± 5.12% vs. 9.6 ± 3.65%, P = 0.038). Those differences were not observed in cord blood leukocytes from the same samples. Conclusions Uncontrolled diabetes during pregnancy disrupts telomere-telomerase homeostasis in the trophoblasts. These changes may increase the risk for metabolic diseases in adulthood among offspring of pregnancies complicated by gestational diabetes mellitus as part of intrauterine programming. These variations were not observed in cord blood leukocytes, which imply different telomere homeostasis mechanisms in fetal cord blood.

Pericentric inversion of one chromosome 9 [inv(9)] is considered a polymorphic variation and is one of the most common forms of autosomal inversion diagnosed prenatally in amniocytes. Yet its clinical significance remains uncertain. Most publications suggest that this finding is insignificant. However, some articles report on abnormal ultrasonic findings in association, such as hydramnios, anhydramnios, hydroureter, hydronephrosis, encephalocele, and prune belly syndrome. Other reports suggest that inv(9) might be one of the etiologies of psychiatric disorders. The homozygote state, on the other hand, is rarely encountered. We report two cases of pericentric inversion of the two homologues of chromosome 9. Two similar cases were previously reported. One affected fetus was had intrauterine growth restriction and the other had Walker-Warburg syndrome as opposed to the normal outcome of our patients. Finally, a workup of this finding is suggested.

Fetal growth restriction (FGR) secondary to placental insufficiency and preeclampsia (PE) are associated with substantially increased childhood and adult morbidity and mortality. The long-term outcomes are related to placental aberrations and intrauterine programming. Advances in microarray technology allow high-resolution, genome-wide evaluation for DNA copy number variations - deletions and duplications. The aim of our study was to demonstrate the usefulness of microarray testing in FGR placentas. Using Affymetrix GeneChip for chromosomal microarray (CMA), we analyzed 10 placentas from pregnancies with FGR attributed to placental insufficiency; 5 with FGR below the 5th percentile and 5 from the 5th to

Heimler syndrome (HS) consists of recessively inherited sensorineural hearing loss, amelogenesis imperfecta (AI) and nail abnormalities, with or without visual defects. Recently HS was shown to result from hypomorphic mutations in PEX1 or PEX6, both previously implicated in Zellweger Syndrome Spectrum Disorders (ZSSD). ZSSD are a group of conditions consisting of craniofacial and neurological abnormalities, sensory defects and multi-organ dysfunction. The finding of HS-causing mutations in PEX1 and PEX6 shows that HS represents the mild end of the ZSSD spectrum, though these conditions were previously thought to be distinct nosological entities. Here, we present six further HS families, five with PEX6 variants and one with PEX1 variants, and show the patterns of Pex1, Pex14 and Pex6 immunoreactivity in the mouse retina. While Ratbi et al. found more HS-causing mutations in PEX1 than in PEX6, as is the case for ZSSD, in this cohort PEX6 variants predominate, suggesting both genes play a significant role in HS. The PEX6 variant c.1802G>A, p.(R601Q), reported previously in compound heterozygous state in one HS and three ZSSD cases, was found in compound heterozygous state in three HS families. Haplotype analysis suggests a common founder variant. All families segregated at least one missense variant, consistent with the hypothesis that HS results from genotypes including milder hypomorphic alleles. The clinical overlap of HS with the more common Usher syndrome and lack of peroxisomal abnormalities on plasma screening suggest that HS may be under-diagnosed. Recognition of AI is key to the accurate diagnosis of HS.

Background Reports on the morphometric analysis of umbilical cord (UC) and its vessels have been inconsistent due to varying inclusion criteria and methodology. The current study tried to overcome the limitations of previous studies by comparing the UC in pregnancies complicated by fetal growth restriction (FGR), preeclampsia (PE) and FGR + PE, to healthy controls. Aims Analyze the morphometric attributes of the UC in pregnancies complicated by FGR and PE. Study design Case–control. Subjects The study groups consisted of 36 patients with FGR + PE, 72 with FGR (without PE) and 15 with PE (without FGR). They were compared to 50 patients without FGR or PE. Outcome measures Histological cross-sections of the UC were photographed and measured. The following variables were recorded: cross-section area of UC, thickness and surface area of umbilical vessel walls, shortest distance between cord surface and nearest artery (DSA), distance between the arteries (DBA) and placental weight and measurements. The area of the Wharton's jelly (WJ) area was calculated. Results UC and WJ cross-section areas were significantly smaller in FGR + PE and FGR, but not in PE. The umbilical vessel wall area was decreased in FGR + PE, but the thickness was not significantly decreased in all three study groups, compared to controls. DSA was smaller in all three groups, whereas DBA was not significantly different, compared to controls. Conclusions Smaller UC cross-section areas were seen in FGR and FGR + PE, but not in PE without FGR. However, there is no evidence to determine whether this reduction is a cause or consequence of FGR. Reduced DSA in PE, whose UC cross-section area was not smaller as in FGR and FGR + PE, might reflect alterations in UC induced by PE.

Objective To describe a method for deciding whether an individual's first-trimester Down syndrome screening test result justifies further testing in the second trimester. Methods Statistical modelling was used to estimate the distribution of second-trimester marker profiles for a given first-trimester profile and hence the probability of a final positive result, using a 1 in 250 term cut-off. A multi-variate log Gaussian model was used with published parameters. Markers were maternal serum pregnancy-associated plasma protein-A and free β-human chorionic gonadotrophin (hCG) at 10 weeks, nuchal translucency at 11 weeks, and second-trimester maternal serum α-fetoprotein, total hCG, unconjugated estriol and inhibin-A. To illustrate the method, the model was applied to a published series of 24 Down syndrome and 367 unaffected pregnancies. Results Modelling predicts that for 63% Down syndrome and 0.4% unaffected pregnancies having first-trimester tests, there is a 50% or more probability of a final positive result. A step-wise sequential screening policy based on immediate prenatal diagnosis for those with high probability and second-trimester testing for the remainder would have a 90% detection rate and 1.7% false-positive rate. Modelling also predicts 8.0% Down syndrome and 89% unaffected pregnancies with probabilities below 3%. A contingent screening policy restricting second-trimester testing to those with 3-49% probabilities would have an 88% detection rate and 1.4% false-positive rate. Conclusion Predicting the probability of a positive final result from the first-trimester marker profile has potential utility, either as a decision aide for individual women or as a formal part of screening policy in selecting a subset of women for second-trimester testing. Copyright © 2005 John Wiley & Sons, Ltd.

Alpha-fetoprotein (AFP) is the main fetus serum glycoprotein with a very low concentration in the adult. AFP deficiency is a rare phenomenon. We studied two families with congenital AFP deficiency and searched for mutations in the AFP gene. We identified one mutation of 2 base deletion in exon 8, in both families, that leads to the congenital deficiency of AFP. The mutation nt930-931delCT (T294fs25X) creates a frameshift after codon 294 that leads to a stop codon after 24 amino acids, thus truncating the normal length of AFP of 609 amino acids. All the affected children were found to be homozygous for the mutation as was one of the fathers. The affected individuals were asymptomatic and presented normal development. This first identification of a mutation in the AFP gene demonstrates for the first time that deficiency of AFP is compatible with human normal fetal development and further reproduction in males.

The syndrome of congenital hypoparathyroidism, mental retardation, facial dysmorphism and extreme growth failure (HRD or Sanjad-Sakati syndrome; OMIM 241410) is an autosomal recessive disorder reported almost exclusively in Middle Eastern populations. A similar syndrome with the additional features of osteosclerosis and recurrent bacterial infections has been classified as autosomal recessive Kenny-Caffey syndrome (AR-KCS; OMIM 244460). Both traits have previously been mapped to chromosome 1q43-44 (refs 5,6) and, despite the observed clinical variability, share an ancestral haplotype, suggesting a common founder mutation. We describe refinement of the critical region to an interval of roughly 230 kb and identification of deletion and truncation mutations of TBCE in affected individuals. The gene TBCE encodes one of several chaperone proteins required for the proper folding of alpha-tubulin subunits and the formation of alpha-beta-tubulin heterodimers. Analysis of diseased fibroblasts and lymphoblastoid cells showed lower microtubule density at the microtubule-organizing center (MTOC) and perturbed microtubule polarity in diseased cells. Immunofluorescence and ultrastructural studies showed disturbances in subcellular organelles that require microtubules for membrane trafficking, such as the Golgi and late endosomal compartments. These findings demonstrate that HRD and AR-KCS are chaperone diseases caused by a genetic defect in the tubulin assembly pathway, and establish a potential connection between tubulin physiology and the development of the parathyroid.

Shortened telomeres reflect genetic instability that might lead to increased aneuploidy and malignant transformations. Chronic hepatitis C (HCV) viral infection is considered a pre-neoplastic condition that might progress to hepatocellular carcinoma. We evaluated telomere length and elongation, in patients with different stages of HCV to study the correlation between telomere length and the progression of HCV.We analyzed peripheral lymphocytes from 10 patients with chronic active HCV, 10 patients with HCV infection in a remission stage, and 10 healthy, age-matched patients, as controls. The expression of hTERT mRNA, which is correlated with elongation of telomeres was measured using RT-PCR and telomere length was analyzed using Q-FISH and a novel computerized technique.hTERT mRNA was significantly decreased in patients with active HCV and slightly decreased in patients who were in remission, compared to healthy individuals. Telomere length was shorter in patients with chronic active HCV and in patients in remission, compared to the healthy controls.There is a correlation between telomerase reverse transcriptase mRNA expression and telomere length in patients with different stages of HCV infection that might be related to the risk of malignant transformation.

We describe a man with pericentric inversion 9 and constitutive heterochromatin, and a high disomy rate in his sperm cells (with all probes analyzed). The disomy rate was estimated with the following probes: 8, 9, 18, X, and Y, and was significantly higher than that in control sperm cells, while chromosome 9 showed the highest disomy frequency. The probes of X and Y together showed the same disomy frequency as X and Y alone, which indicates the same nondisjunction rate in the first meiotic division. We suggest that the interchromosomal effect found in this man differed from other findings in sperm cells of men carrying an inversion in terms of the difference in the length of the heterochromatin between the two chromosomes 9. Also, it is well known that the effect of inversion 9 with increased heterochromatin is highly variable and may even vary in members of the same family.

The fetal cerebellar structure, size and consistency are looked at in every system survey. Among the acquired cerebellar events that might change the cerebellar consistency are haemorrhage, infections in utero and neoplasia. Additional fetal malformations, if present, assist in making the final diagnosis. We present a case of an isolated echogenic mass in one of the cerebellar hemispheres along with the differential diagnosis.

We report the first known case in Israel of a patient with an early childhood onset of ceroid-lipofuscinosis who is homozygous to a mutation of the CLN8 gene. This patient further expands the clinical varieties of CLN8, initially reported in Finland and Turkey and recently in Italy. The ultrastructural pathology of a skin biopsy specimen revealed abundant typical fingerprint profiles, but rare granular osmiophilic bodies and curvilinear structures. Sequencing of exon 3 of the CLN8 gene revealed a novel C>G missense mutation at a conserved amino acid glutamine 256 to glutamic acid. Our findings further raise the possibility of the existence of a Mediterranean CLN8 variant.

A study of the association between aneuploidy and fetal choroid plexus cysts (CPCs) is presented. By reviewing the world prospective and retrospective studies, one cannot reach an agreed conclusion since different study designs were used and meta analysis is not feasible. Our experience is that as a solitary ultrasonographic finding, genetic evaluation is not indicated in cases of CPC. However, all the 'risk factors' of fetal aneuploidy such as maternal age, biochemical markers, and ultrasonographic signs may create a score by which the indication for genetic evaluation will be more sound.

Background. A correlation between prenatal and postnatal penile and clitoral sizes has not been reported. These data would substantiate the ability of prenatal ultrasound (US) scan to predict postnatal measurements. The aims were to correlate prenatal and postnatal penile and clitoral measurements and to ascertain the possible advantage of using prenatal penile width rather than length to predict postnatal measurements. Methods. This was a longitudinal study. Fetal penis and clitoris were measured by high-resolution US between gestational weeks 14 and 29. Postnatal measurements of external genitalia were performed during the first postnatal week. All measurements were performed twice consecutively. A correlation between the measurements sets was sought. Results. Paired prenatal and postnatal measurements were performed on 46 males and 48 females. Prenatal penile and clitoral length values correlated significantly with postnatal length at p < 0.05 each. Conclusions. Prenatal US findings appear to be reliable indicators of postnatal penile and clitoral length measurements. Penile width measurement did not add new information. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound 40:394–398, 2012

Intrauterine fetal movement plays a key role in normal embryonic and fetal development (Moessinger, 1983). When movement is absent or decreased, abnormal development takes place which can be appreciated in newborns and/or fetuses with the fetal akinesia/ hypokinesia sequence. This sequence is caused by a number of heterogeneous entities which result in decreased fetal movements by the action of intrinsic or extrinsic factors. Prenatal diagnosis of the akinesia/hypokinesia sequence may be possible during the second trimester through the use of real-time ultrasonographic evaluation of fetal movement. We report a family with three consecutive affected pregnancies in which the prenatal presentation of this sequence varied. Based on the phenotypic findings of the three affected fetuses, we believe that although they superficially resemble those features found in the New–Laxova syndrome, they are probably affected with a distinctly different lethal form of akinesia/ hypokinesia transmitted in an autosomal recessive fashion.

It is well known that prenatal exposure of valproic acid (VPA) may be associated with the occurrence of neural tube defects (Robert and Gibaud, 1982). Additional adverse effects related to VPA exposure include craniofacial abnormalities, skeletal defects, brain defects, cardiovascular defects, and urogenital defects (DiLiberti et al., 1984; Winter et al., 1987; Huot et al., 1987; Jager-Roman et al., 1986; Martinez-Frias, 1990). Recently, radial ray reduction has been reported as a severe type of skeletal defect associated with VPA exposure (Jager-Roman et al., 1986; Huot et al., 1987; Verloes et al., 1990). We report two additional cases of this severe limb reduction defect as part of a broader pattern of altered morphogenesis in fetuses exposed to VPA and to confirm an association between such severe specific skeletal defects and VPA exposure. We briefly review teratologic studies in experimental animals which document the biologic plausibility of this association, and suggest that fetuses exposed to VPA undergo detailed prenatal ultrasonographic evaluation of the limbs.

Objective : We examined the accuracy of prenatal diagnosis of skeletal dysplasias and ways to refine this ability. Study design : A total of 226 fetuses and stillbirths referred for suspected skeletal dysplasia were evaluated. The fetal age, mode of ascertainment, and referring diagnosis were analyzed with regard to the final diagnosis. Results : The leading mode of diagnosis was routine ultrasonography performed between 16 and 24 weeks' gestation. Twenty-two cases (9.7%) had previous sibs, parents, or cousins affected. The most common final diagnosis was osteogenesis imperfecta. In 15 cases (7%) the fetus did not appear to have a skeletal dysplasia or an obvious dysmorphic syndrome. Conclusions : Prenatal diagnosis of skeletal dysplasia can be made as early as 14 weeks. Most cases are sporadic. Fetal radiographs help in reaching an accurate diagnosis or at least in identifying the probable lethal disorders.