Choosing between Higher and Lower Resolution Microarrays: do Pregnant Women Have Sufficient Knowledge to Make Informed Choices Consistent with their Attitude?

Developments in prenatal testing allow the detection of more findings. SNP arrays in prenatal diagnosis (PND) can be analyzed at 0.5 Mb resolution detecting more clinically relevant anomalies, or at 5 Mb resolution. We investigated whether women had sufficient knowledge to make informed choices regarding the scope of their prenatal test that were consistent with their attitude. Pregnant women could choose between testing at 5 or at 0.5 Mb array. Consenting women (N = 69) received pre-test genetic counseling by phone and filled out the Measure of Informed Choice questionnaire designed for this study. Choices based on sufficient knowledge and consistent with attitude were considered informed. Sixty-two percent of the women made an adequately informed choice, based on sufficient knowledge and attitude-consistent with their choice of microarray resolution. Women who made an informed choice, opted for 0.5 Mb array resolution more often. There were no differences between women making adequately informed or less informed choices regarding level of experienced anxiety or doubts. Over time on T0 and T1, anxiety and doubts significantly decreased. While previous studies demonstrated that knowledge is an important component in informed decision-making, this study underlines that a consistent attitude might be equally important for decision-making. We advocate more focus on attitude-consistency and deliberation as compared to only a strong focus on knowledge.

[What if the sperm donor has a hereditary disease? Informed consent needed for sharing medical information]. / Wat als de zaaddonor een erfelijke ziekte heeft?

There are no regulations in the Netherlands regarding the exchange of important genetic information that has become available after the birth of a child conceived with donor gametes. This may lead to difficult situations such as when the gamete donor is found to suffer from a genetic cancer-predisposition disorder. Genetic information about the donor that becomes available later may be of great importance to donor offspring. Genetic information uncovered in the donor child may likewise be of importance to legal offspring of the gamete donor. We propose an informed-consent procedure for both donors and recipients to take better care of this issue.

Prenatal and postnatal findings in small-for-gestational-age fetuses without structural ultrasound anomalies at 18-24 weeks.

OBJECTIVE: To assess phenotypic and genotypic characteristics of small-for-gestational-age (SGA) fetuses without structural anomalies at 18-24 weeks' gestation. METHODS: This retrospective study included structurally normal singleton fetuses with an abdominal circumference ≤ 5th percentile on detailed ultrasound examination between 18 and 24 weeks' gestation. Cases were stratified according to the absence or presence of other abnormal ultrasound findings, such as abnormal amniotic fluid or soft markers. All patients were offered invasive prenatal testing with rapid aneuploidy detection by qualitative fluorescence polymerase chain reaction (QF-PCR) and, if normal, consecutive single nucleotide polymorphism (SNP) array was also offered. Detailed postnatal follow-up (≥ 5 months) was performed. In cases in which a syndromic phenotype became apparent within 5 months after birth and SNP array had not been performed prenatally, it was performed postnatally. RESULTS: A total of 211 pregnancies were eligible for inclusion. Of the 158 cases with isolated SGA on ultrasound, 36 opted for invasive prenatal testing. One case of trisomy 21 and one case of a submicroscopic abnormality (a susceptibility locus for neurodevelopmental disease) were detected. Postnatal follow-up showed a postnatal apparent syndromic phenotype in 10 cases. In one case this was due to trisomy 21 and the other nine (5.8%; 95% CI, 2.8-10.0%) cases had normal SNP array results. In 32/53 cases with SGA and associated ultrasound abnormalities, parents opted for invasive testing. One case of trisomy 21 and one of triploidy were found. In 11 cases a syndromic phenotype became apparent after birth. One was due to trisomy 21 and in one case a submicroscopic anomaly (a susceptibility locus) was found. The remaining syndromic cases (17.3%; 95% CI, 8.7-29.0%) had normal SNP array results. CONCLUSION: Testing for chromosomal anomalies should be offered in cases of SGA between 18 and 24 weeks' gestation. Whole chromosome anomalies occur in 1.3% (95% CI, 0.2-3.9%) of isolated SGA and 5.8% (95% CI, 1.5-14.0%) of associated SGA. In 0.6% (95% CI, 0.1-2.8%) and 1.9% (95% CI, 0.2-8.2%), respectively, SNP array detected a susceptibility locus for neurodevelopmental disease that would not be detected by karyotyping, QF-PCR or non-invasive prenatal testing. Therefore, and because the genetic causes of SGA are diverse, we suggest SNP array testing in cases of SGA. Thorough postnatal examination and follow-up of infants that presented with reduced fetal growth is important because chromosomally normal syndromic phenotypes occur frequently in SGA fetuses. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

The Psychological Impact of Prenatal Diagnosis and Disclosure of Susceptibility Loci: First Impressions of Parents' Experiences.

Genomic microarray may detect susceptibility loci (SL) for neurodevelopmental disorders such as autism and epilepsy, with a yet unquantifiable risk for the fetus. The prenatal disclosure of susceptibility loci is a topic of much debate. Many health care professionals fear that reporting susceptibility loci may put a psychological burden on pregnant couples. It is our policy to disclose prenatal susceptibility loci as we recognize them as actionable for prospective parents. The aim of this report was to evaluate the psychological impact of disclosing a prenatal diagnosis of susceptibility loci. The psychological impact of disclosing susceptibility loci was evaluated in the first patients who received such results. Eight out of 15 women who had a susceptibility locus disclosed and four of their partners consented to share their experiences through a telephonic evaluation (n = 12). Follow-up time ranged from 3 to 15 months after their prenatal test result. The reporting of susceptibility loci was initially 'shocking' for five parents while the other seven felt 'worried'. Ten out of 12 participants indicated they would like to be informed about the susceptibility locus again, two were unsure. Most had no enduring worries. Participants unanimously indicated that pregnant couples should have an individualized pre-test choice about susceptibility loci (non)disclosure. We observed no negative psychological impact with the prenatal diagnosis and disclosure of SL on participants. A key factor in mitigating parental anxiety with SL disclosure appears to be post-test genetic counseling. Our report confirms that pregnant women and their partners prefer an individualized choice regarding the scope of prenatal testing.

Pregnant couples at increased risk for common aneuploidies choose maximal information from invasive genetic testing.

Genomic array detects more pathogenic chromosome aberrations than conventional karyotyping (CK), including genetic variants associated with a susceptibility for neurodevelopmental disorders; susceptibility loci (SL). Consensus regarding the scope of invasive prenatal diagnosis (PND) pregnant couples should be offered is lacking. This study examined pregnant couples' preferences, doubts and satisfaction regarding the scope of invasive PND. Eighty-two couples choosing prenatal screening (PNS) and 59 couples choosing invasive PND were offered a choice between 5 (comparable to CK) and 0.5 Mb resolution array analysis outcomes, the latter with or without reporting SL. A pre-test self-report questionnaire and post-test telephone interview assessed their choices in-depth. Actual (PND) and hypothetical (PNS) choices differed significantly (p < 0.001). Ninety-five percent of the couples in the PND group chose 0.5 Mb array, vs 69% in the PNS group. Seven percent of the PND group wished not to be informed of SL. Ninety percent was satisfied with their choice and wished to decide about the scope themselves. Pregnant couples wish to make their own choices regarding the scope of invasive PND. It therefore seems justified to offer them a choice in both the resolution of array and disclosure of SL.

Additional value of prenatal genomic array testing in fetuses with isolated structural ultrasound abnormalities and a normal karyotype: a systematic review of the literature.

OBJECTIVE: To establish the prevalence of submicroscopic genetic copy number variants (CNVs) in fetuses with a structural ultrasound anomaly (restricted to one anatomical system) and a normal karyotype. The aim was to determine the diagnostic and prognostic value of genomic array testing in these pregnancies. METHODS: Embase and PubMed databases were systematically searched for all relevant articles on prevalence of pathogenic submicroscopic CNVs in fetuses with ultrasound anomalies. Reported cases were sorted into groups according to anatomical site of the detected ultrasound anomaly. The prevalence of causative submicroscopic CNVs was calculated for each group. RESULTS: Combined data of the reviewed studies (n = 18) indicated that fetuses with an ultrasound anomaly restricted to one anatomical system (n = 2220) had a 3.1-7.9% chance of carrying a causative submicroscopic CNV, depending on the anatomical system affected. This chance increased to 9.1% for fetuses with multiple ultrasound anomalies (n = 1139). CONCLUSION: This review indicates that 3.1-7.9% of fetuses with a structural ultrasound anomaly restricted to one anatomical system and a normal karyotype will show a submicroscopic CNV, which explains its phenotype and provides information for fetal prognosis. Therefore, we conclude that microarray has considerable diagnostic and prognostic value in these pregnancies.

Outcome of pregnancies complicated by oligohydramnios or anhydramnios of renal origin.

OBJECTIVE: To evaluate the outcome of fetuses with oligohydramnios due to kidney anomalies. METHODS: A retrospective study was performed of all pregnancies diagnosed with oligohydramnios and associated kidney anomalies during the period 2000-2008. Outcome included pregnancy outcome, mortality, and morbidity. Morbidity included renal function based on the glomerular filtration rate (GFR) during follow-up. RESULTS: A total of 71 pregnancies were evaluated; 36 fetuses presented on ultrasound with cystic dysplasia, 15 with polycystic kidney disease (PKD) and 20 with hydronephrosis. Twenty-three (32%) had associated anomalies. In 49 fetuses (69%), the diagnosis had been made before 24 weeks of gestational age (GA); 41 of those pregnancies were terminated. Twenty-five neonates were live born: 10 survived, 15 died. Prognostic factors for survival included GA at diagnosis (32.2 weeks for survivors vs 28.1 weeks for non-survivors; P = 0.02), diagnosis of hydronephrosis (7 in the survivors vs 4 in the non-survivors: P = 0.05), isolated anomaly (9 in the survivors vs 7 in the non-survivors: P = 0.04). Severity of oligohydramnios (1 case of anhydramnios in the survivors vs 7 in the non-survivors: P = 0.08) was not significant. The 1-year GFR was below 50 mL/min.1.73 m(2) in four of the ten survivors. CONCLUSION: The prognosis of early onset renal oligohydramnios is poor. Predictive determinants of survival are: GA at diagnosis, nature of renal anomaly (hydronephrosis vs other), and presence of associated anomalies.

Omphalocele: comparison of outcome following prenatal or postnatal diagnosis.

OBJECTIVES: To assess the impact of prenatal compared with postnatal diagnosis on outcome for liveborn infants with an isolated or with a non-isolated omphalocele. METHODS: This was a retrospective analysis of 101 prenatally and 45 postnatally diagnosed cases of omphalocele. Cases were collected from the ultrasound database of the Division of Obstetrics and Prenatal Medicine and the patient database of the Department of Pediatric Surgery. RESULTS: Following confirmation at delivery or autopsy, prenatally diagnosed omphaloceles included 21 isolated cases, 44 non-isolated cases with a normal karyotype and 36 non-isolated cases with an abnormal karyotype. Of the prenatally diagnosed apparently isolated cases (n = 31), 12 (39%; 95% CI, 22-58%) revealed associated anomalies after delivery. Liveborn infants with an isolated omphalocele had significantly worse short-term morbidity following prenatal diagnosis (n = 14) compared with diagnosis at birth (n = 29), having a lower gestational age at delivery, lower Apgar scores, longer duration of ventilation and parenteral nutrition, more readmissions and a longer hospital stay. The prenatally diagnosed subset contained more infants with a giant omphalocele (9/14 vs. 3/29, P = 0.001) and liver herniation (8/14 vs. 6/29, P = 0.02). The outcome of liveborn infants with a non-isolated omphalocele diagnosed prenatally (n = 17) was not different from that of those diagnosed at birth (n = 16), except for a greater need for ventilation and parenteral nutrition in the prenatal subset. CONCLUSION: When counseling patients with a prenatal diagnosis of isolated omphalocele, it is important to remember that over one third could turn out to have associated anomalies. Liveborn infants with an isolated omphalocele detected prenatally have worse short-term morbidity than do cases detected at birth. Those with non-isolated omphaloceles detected prenatally have an increased need for ventilation and parenteral nutrition compared with those detected at birth.

Phenotype-genotype correlation in a familial IGF1R microdeletion case.

BACKGROUND: IGF1R (insulin-like growth factor 1 receptor) haploinsufficiency is a rare event causing difficulties in defining clear genotype-phenotype correlations, although short stature is its well established hallmark. Several pure 15q26 monosomies (n=22) have been described in the literature, including those with breakpoints proximal to the IGF1R gene. Clinical heterogeneity is characteristic for these mainly de novo telomeric deletions and is illustrated by the involvement of several different organ systems such as the heart, diaphragm, lungs, kidneys and limbs, besides growth failure in the patient's phenotype. The clinical variability in these patients could be explained by the haploinsufficiency of multiple genes besides the IGF1R gene. In comparison, the six different IGF1R mutations revealed to date exhibit some variance in their clinical features as well, probably because different parts of the downstream IGF1R signalling cascade were affected. METHODS AND RESULTS: Using the recently developed technique multiplex ligation dependent probe amplification (MLPA), a chromosome 15q26.3 microdeletion harbouring part of the IGF1R gene was identified in a Dutch family. This deletion segregated with short height in seven out of 14 relatives across three generations. Metaphase fluorescence in situ hybridisation (FISH) and Affymetrix 250k single nucleotide polymorphism (SNP) microarray were used to characterise the deletion into more detail and showed that exons 11-21 of the IGF1R and a small hypothetical protein (LOC 145814) were deleted. CONCLUSION: Clinical work-up of this newly identified family, which constitutes the smallest (0.095 Mb) pure 15q26.3 interstitial deletion to date, confirms that disruption of the IGF1R gene does not induce major organ malformation or severe mental retardation.

A genome-wide linkage scan in a Dutch family identifies a premature ovarian failure susceptibility locus.

BACKGROUND: Premature ovarian failure (POF) is characterized by elevated gonadotrophins and amenorrhea before the age of 40 years and occurs approximately in 1% of women. POF etiology is highly heterogeneous with a wide spectrum of etiological pathogenic mechanisms including genetic causes. These mostly involve numerical, structural or monogenic defects on the X-chromosome. Mutations in a small number of autosomal genes (such as FOXL2 and NOBOX) have been identified as a cause of POF. However, in most cases, the disease underlying mechanisms are largely unknown. METHODS: We performed a genome-wide linkage analysis in a relatively large Dutch family with seven patients suffering from POF, showing a dominant pattern of inheritance. A genome-wide analysis, using 50K single nucleotide polymorphism arrays, was combined with conventional parametric linkage analysis. RESULTS: We identified three genomic regions on chromosomes 5, 14 and 18 yielding suggestive linkage (multipoint LOD score of 2.4 for each region). After inclusion of one elder unaffected family member, only the region on chromosome 5 remains as a putative POF locus. In addition, we investigated a second family (three living patients over three generations) for the regions on chromosome 5, 14 and 18. Haplotype analysis supported only the locus on chromosome 5q14.1-q15. CONCLUSION: We performed the first genome-wide linkage search in familial POF and identified a region on chromosome 5q14.1-q15, which may harbor a novel POF susceptibility gene.

Savings and extinction of conditioned eyeblink responses in fragile X syndrome.

The fragile X syndrome (FRAXA) is the most widespread heritable form of mental retardation caused by the lack of expression of the fragile X mental retardation protein (FMRP). This lack has been related to deficits in cerebellum-mediated acquisition of conditioned eyelid responses in individuals with FRAXA. In the present behavioral study, long-term effects of deficiency of FMRP were investigated by examining the acquisition, savings and extinction of delay eyeblink conditioning in male individuals with FRAXA. In the acquisition experiment, subjects with FRAXA displayed a significantly poor performance compared with controls. In the savings experiment performed at least 6 months later, subjects with FRAXA and controls showed similar levels of savings of conditioned responses. Subsequently, extinction was faster in subjects with FRAXA than in controls. These findings confirm that absence of the FMRP affects cerebellar motor learning. The normal performance in the savings experiment and aberrant performance in the acquisition and extinction experiments of individuals with FRAXA suggest that different mechanisms underlie acquisition, savings and extinction of cerebellar motor learning.

Facial and pituitary morphology are related in Dutch patients with GH deficiency.

OBJECTIVE: Classical GH deficiency (GHD) is associated with typical phenotypic features. We have analysed standardized photographs of 137 Caucasian patients with GHD, in order to examine the relations between auxological, biochemical, pituitary and facial morphometric features. PATIENTS AND MEASUREMENTS: We analysed pictures of 137 patients: 73 (55 Males/18 Females) with Isolated GHD and 64 (48 M/16 F) with multiple pituitary hormone deficiency (MPHD). Of each patient, standardized frontal and lateral digital pictures were taken and analysed using Adobe Photoshop 5.0. RESULTS: Canthal index (CI), the relative distance between the eyes, was related to pituitary morphology. Patients with an ectopic posterior pituitary (EPP) had significantly higher CI values than patients without EPP. We found CI > 39 to be a good cut-off value to select children with highest probability of having EPP. The combination of CI > 39 with the presence of hormonal deficiencies additional to GHD strongly predicted EPP: 93% of the patients with a CI > 39 and additional hormonal deficiencies had EPP, in contrast to 77% of the patients with additional hormonal deficiencies but a CI < 39, and 29% of the patients with none of these criteria (P = 0.0001). CONCLUSION: CI, measured on digital pictures, is associated with ectopia of the posterior pituitary and this might be caused by an altered midline development, affecting both the pituitary and the facial structures of GHD patients.

Exceptional good cognitive and phenotypic profile in a male carrying a mosaic mutation in the FMR1 gene.

Fragile X (FRAX) syndrome is a commonly inherited form of mental retardation resulting from the lack of expression of the fragile X mental retardation protein (FMRP). It is caused by a stretch of CGG repeats within the fragile X gene, which can be unstable in length as it is transmitted from generation to generation. Once the repeat exceeds a threshold length, the FMR1 gene is methylated and no protein is produced resulting in the fragile X phenotype. The consequences of FMRP absence in the mechanisms underlying mental retardation are unknown. We have identified a male patient in a classical FRAX family without the characteristic FRAX phenotype. His intelligence quotient (IQ) is borderline normal despite the presence of a mosaic pattern of a pre-mutation (25%), full mutation (60%) and a deletion (15%) in the FMR1 gene. The cognitive performance was determined at the age of 28 by the Raven test and his IQ was 81. However, FMRP expression studies in both hair roots and lymphocytes, determined at the same time as the IQ test, were within the affected male range. The percentage of conditioned responses after delay eyeblink conditioning was much higher than the average percentage measured in FRAX studies. Moreover, this patient showed no correlation between FMRP expression and phenotype and no correlation between DNA diagnostics and phenotype.

[Pathogenesis of Alzheimer's disease: molecular and cellular mechanisms]. / Pathogénie de la maladie d'Alzheimer: les mécanismes moléculaires et cellulaires.

Alzheimer's disease is worldwide the leading cause of dementia in the elderly. Senile plaques and neurofibrillary tangles are together with neuronal loss and cortical atrophy characteristic neuropathological features of the disease. Senile plaques contain beta-amyloid (Abeta) peptide which is produced by cleavage of the amyloid precursor protein (APP) by beta- and gamma-secretases. Neurofibrillary tangles are twisted helicoidal strands of hyperphosphorylated tau protein, a microtubule-associated protein. Both pathogenic arms which we describe are interrelated and Abeta deposition seems to potentiate tau pathology. Tangle and plaque formation is influenced by various factors including reciprocal interactions, genetic factors, inflammation and reactive oxygen species. A better understanding of the cellular and molecular cascade which leads to the neuropathological lesions of Alzheimer's disease has led to novel disease-modifying treatment strategies. They yield varying, though encouraging, results and target various stages of the pathological process. Future cooperation between basic, clinical and pharmacological research should allow the development in a foreseeable future of strategies that can halt, or even prevent, this devastating disorder.

Contribution of CYLN2 and GTF2IRD1 to neurological and cognitive symptoms in Williams Syndrome.

Williams Syndrome (WS, [MIM 194050]) is a disorder caused by a hemizygous deletion of 25-30 genes on chromosome 7q11.23. Several of these genes including those encoding cytoplasmic linker protein-115 (CYLN2) and general transcription factors (GTF2I and GTF2IRD1) are expressed in the brain and may contribute to the distinct neurological and cognitive deficits in WS patients. Recent studies of patients with partial deletions indicate that hemizygosity of GTF2I probably contributes to mental retardation in WS. Here we investigate whether CYLN2 and GTF2IRD1 contribute to the motoric and cognitive deficits in WS. Behavioral assessment of a new patient in which STX1A and LIMK1, but not CYLN2 and GTF2IRD1, are deleted showed that his cognitive and motor coordination functions were significantly better than in typical WS patients. Comparative analyses of gene specific CYLN2 and GTF2IRD1 knockout mice showed that a reduced size of the corpus callosum as well as deficits in motor coordination and hippocampal memory formation may be attributed to a deletion of CYLN2, while increased ventricle volume can be attributed to both CYLN2 and GTF2IRD1. We conclude that the motor and cognitive deficits in Williams Syndrome are caused by a variety of genes and that heterozygous deletion of CYLN2 is one of the major causes responsible for such dysfunctions.

Visual depth processing in Williams-Beuren syndrome.

Patients with Williams-Beuren Syndrome (WBS, also known as Williams Syndrome) show many problems in motor activities requiring visuo-motor integration, such as walking stairs. We tested to what extent these problems might be related to a deficit in the perception of visual depth or to problems in using this information in guiding movements. Monocular and binocular visual depth perception was tested in 33 patients with WBS. Furthermore, hand movements to a target were recorded in conditions with and without visual feedback of the position of the hand. The WBS group was compared to a group of control subjects. The WBS patients were able to perceive monocular depth cues that require global processing, but about 49% failed to show stereopsis. On average, patients with WBS moved their hand too far when no visual feedback on hand position was given. This was not so when they could see their hand. Patients with WBS are able to derive depth from complex spatial relationships between objects. However, they seem to be impaired in using depth information for guiding their movements when deprived of visual feedback. We conclude that the problems that WBS patients have with tasks such as descending stairs are not due to an inability to judge distance.

Familial insertion (3;5)(q25.3;q22.1q31.3) with deletion or duplication of chromosome region 5q22.1-5q31.3 in ten unbalanced carriers.

We report on the clinical and cytogenetic data of a large family with an unbalanced insertion translocation (3;5)(q25.3;q22.1q31.3). Analysis of GTG-banded chromosomes demonstrated that unbalanced inheritance of a parental insertion translocation caused either a partial deletion or duplication 5q in this family. The derivative chromosomes were characterized further using microdissection and FISH with band-specific probes. The clinical picture of the proband with a partial deletion of chromosome 5 was characterized by moderate psychomotor retardation, mild facial dysmorphism, cleft palate, and single transverse crease. The family members with a partial duplication of chromosome 5 were borderline intelligent, had mild facial dysmorphism, a cardiac anomaly, and a high-pitched voice. The unbalanced carriers were compared with patients reported in the literature with a duplication or deletion of chromosome region 5q22.1 --> 5q31.3.

Saccade dysmetria in Williams-Beuren syndrome.

Numerous studies have described the poor visuo-spatial processing capacities of subjects with Williams-Beuren syndrome (WBS), a genetically based developmental disorder. Since visual perception and eye movements are closely related we hypothesized that the poor visuo-spatial processing capacities of subjects with WBS might be related to a poor saccadic control. Thereto, we recorded horizontal and vertical saccadic eye movements to targets using infrared video-oculography in 27 subjects with WBS and eight healthy controls. In the WBS group saccadic gains were highly variable, both between and within individual subjects, and they often needed more than one correction saccade to reach the target. Ten (out of a subgroup of 22) WBS subjects showed a large number of hypometric and/or hypermetric saccades, and, also a left-right asymmetry in saccadic gains was observed in WBS. We conclude that the observed impairments in saccadic control are likely to affect the proper processing of visuo-spatial information.