Phenotype-to-Genotype Description of Prenatal Suspected and Postnatal Discovered Upper Limb Anomalies: A Retrospective Cohort Study.

Objective: To evaluate phenotype and genotype characteristics of fetuses and children with upper limb anomalies.

Method: Retrospective cohort study of a prenatal and postnatal cohort with upper limb anomalies from January 2007 to December 2021 in a Fetal Medicine Unit. Prenatally on ultrasound suspected upper limb anomalies, such as transverse and longitudinal reduction defects, polydactyly, and syndactyly, and postnatally identified children referred to the Congenital Hand Team were evaluated separately.

Efficacy and Toxicity of Calcitonin Treatment in Children with Cherubism: A Single-Center Cohort Study.

Cherubism is a rare autosomal dominant disease characterized by expansile osteolytic jawbone lesions. The effect and safety of off-label calcitonin treatment during the progressive phase of the disease are not well described. In this retrospective study, we present data on the radiological response and adverse effects of subcutaneously administered calcitonin in a cohort of nine cherubism children (three female, six male).

Clinical impact of additional findings detected by genome-wide non-invasive prenatal testing: Follow-up results of the TRIDENT-2 study.

In the TRIDENT-2 study, all pregnant women in the Netherlands are offered genome-wide non-invasive prenatal testing (GW-NIPT) with a choice of receiving either full screening or screening solely for common trisomies. Previous data showed that GW-NIPT can reliably detect common trisomies in the general obstetric population and that this test can also detect other chromosomal abnormalities (additional findings). However, evidence regarding the clinical impact of screening for additional findings is lacking.

Increased nuchal translucency before 11 weeks of gestation: Reason for referral?

Objectives: In this era of non-invasive-prenatal testing (NIPT), when dating scans are usually performed around 10 weeks of gestation, an increased NT before the official established timeframe (CRL between 45 and 84 mm) may be encountered. Information on management of these pregnancies is limited. Therefore, we evaluated the relationship between an early increased NT and adverse pregnancy outcome.

Rapid whole exome sequencing in pregnancies to identify the underlying genetic cause in fetuses with congenital anomalies detected by ultrasound imaging.

Objective: The purpose of this study was to explore the diagnostic yield and clinical utility of trio-based rapid whole exome sequencing (rWES) in pregnancies of fetuses with a wide range of congenital anomalies detected by ultrasound imaging.

Methods: In this observational study, we analyzed the first 54 cases referred to our laboratory for prenatal rWES to support clinical decision making, after the sonographic detection of fetal congenital anomalies. The most common identified congenital anomalies were skeletal dysplasia (n = 20), multiple major fetal congenital anomalies (n = 17) and intracerebral structural anomalies (n = 7).

TRIDENT-2: National Implementation of Genome-wide Non-invasive Prenatal Testing as a First-Tier Screening Test in the Netherlands.

The Netherlands launched a nationwide implementation study on non-invasive prenatal testing (NIPT) as a first-tier test offered to all pregnant women. This started on April 1, 2017 as the TRIDENT-2 study, licensed by the Dutch Ministry of Health. In the first year, NIPT was performed in 73,239 pregnancies (42% of all pregnancies), 7,239 (4%) chose first-trimester combined testing, and 54% did not participate.

An inactivating mutation in the histone deacetylase SIRT6 causes human perinatal lethality.

It has been well established that histone and DNA modifications are critical to maintaining the equilibrium between pluripotency and differentiation during early embryogenesis. Mutations in key regulators of DNA methylation have shown that the balance between gene regulation and function is critical during neural development in early years of life. However, there have been no identified cases linking epigenetic regulators to aberrant human development and fetal demise.

Mosaic maternal 10qter deletions are associated with FRA10B expansions and may cause false-positive noninvasive prenatal screening results.

Purpose: Using genome-wide noninvasive prenatal screening (NIPS), we detected a 20-megabase specific deletion starting at 10q25 in eight pregnancies. The deletion could not be confirmed by invasive testing. Since all 10(q25→qter) deletions started close to the FRA10B fragile site in 10q25, we investigated whether the pregnant women were indeed carriers of FRA10B.

Preconception carrier screening for multiple disorders: evaluation of a screening offer in a Dutch founder population.

Technological developments have enabled carrier screening for multiple disorders. This study evaluated experiences with a preconception carrier screening offer for four recessive disorders in a Dutch founder population. Questionnaires were completed by 182 attendees pretesting and posttesting and by 137 non-attendees.

Origin and clinical relevance of chromosomal aberrations other than the common trisomies detected by genome-wide NIPS: results of the TRIDENT study.

PurposeNoninvasive prenatal screening (NIPS) using cell-free DNA in maternal blood is highly sensitive for detecting fetal trisomies 21, 18, and 13. Using a genome-wide approach, other chromosome anomalies can also be detected. We report on the origin, frequency, and clinical significance of these other chromosome aberrations found in pregnancies at risk for trisomy 21, 18, or 13.

Women's Experience with Non-Invasive Prenatal Testing and Emotional Well-being and Satisfaction after Test-Results.

Increasingly, high-risk pregnant women opt for non-invasive prenatal testing (NIPT) instead of invasive diagnostic testing. Since NIPT is less accurate than invasive testing, a normal NIPT result might leave women less reassured. A questionnaire study was performed among pregnant women with elevated risk for fetal aneuploidy based on first-trimester combined test (risk ≥1:200) or medical history, who were offered NIPT in the nationwide Dutch TRIDENT study.

With expanded carrier screening, founder populations run the risk of being overlooked.

Genetically isolated populations exist worldwide. Specific genetic disorders, including rare autosomal recessive disorders may have high prevalences in these populations. We searched for Dutch genetically isolated populations and their autosomal recessive founder mutations.

Trial by Dutch laboratories for evaluation of non-invasive prenatal testing. Part II-women's perspectives.

Objective: To evaluate preferences and decision-making among high-risk pregnant women offered a choice between Non-Invasive Prenatal Testing (NIPT), invasive testing or no further testing.

Methods: Nationwide implementation study (TRIDENT) offering NIPT as contingent screening test for women at increased risk for fetal aneuploidy based on first-trimester combined testing (>1:200) or medical history. A questionnaire was completed after counseling assessing knowledge, attitudes and participation following the Multidimensional Measure of Informed Choice.

Factors for successful implementation of population-based expanded carrier screening: learning from existing initiatives.

Background: Carrier screening for autosomal recessive disorders aims to facilitate reproductive decision-making by identifying couples with a 1-in-4 risk in every pregnancy of having an affected child. Except for a few countries or regions, carrier screening is not widely offered and is mostly ancestry-based. Technological advances enable carrier screening for multiple diseases simultaneously allowing universal screening regardless of ancestry (population-based expanded carrier screening).

A Dutch family with autosomal recessively inherited lower motor neuron predominant motor neuron disease due to optineurin mutations.

Approximately 10% of motor neuron disease (MND) patients report a familial predisposition for MND. Autosomal recessively inherited MND is less common and is most often caused by mutations in the superoxide dismutase 1 (SOD1) gene. In 2010, autosomal recessively inherited mutations in the optineurin (OPTN) gene were found in 1% of Japanese patients with sporadic amyotrophic lateral sclerosis (ALS).

Do people from the Jewish community prefer ancestry-based or pan-ethnic expanded carrier screening?

Ancestry-based carrier screening in the Ashkenazi Jewish population entails screening for specific autosomal recessive founder mutations, which are rarer among the general population. As it is now technically feasible to screen for many more diseases, the question arises whether this population prefers a limited ancestry-based offer or a pan-ethnic expanded carrier screening panel that goes beyond the diseases that are frequent in their own population, and is offered regardless of ancestry. An online questionnaire was completed by 145 individuals from the Dutch Jewish community (≥ 18 years) between April and July 2014.

Targeted carrier screening for four recessive disorders: high detection rate within a founder population.

In a genetically isolated community in the Netherlands four severe recessive genetic disorders occur at relatively high frequency (pontocerebellar hypoplasia type 2 (PCH2), fetal akinesia deformation sequence (FADS), rhizomelic chondrodysplasia punctata type 1 (RCDP1), and osteogenesis imperfecta (OI) type IIB/III. Over the past decades multiple patients with these disorders have been identified. This warranted the start of a preconception outpatient clinic, in 2012, aimed at couples planning a pregnancy.

A new mutation for Huntington disease following maternal transmission of an intermediate allele.

New mutations for Huntington disease (HD) originate from CAG repeat expansion of intermediate alleles (27-35 CAG). Expansions of such alleles into the pathological range (≥ 36 CAG) have been exclusively observed in paternal transmission. We report the occurrence of a new mutation that defies the paternal expansion bias normally observed in HD.

Exome sequencing identifies DYNC2H1 mutations as a common cause of asphyxiating thoracic dystrophy (Jeune syndrome) without major polydactyly, renal or retinal involvement.

Background: Jeune asphyxiating thoracic dystrophy (JATD) is a rare, often lethal, recessively inherited chondrodysplasia characterised by shortened ribs and long bones, sometimes accompanied by polydactyly, and renal, liver and retinal disease. Mutations in intraflagellar transport (IFT) genes cause JATD, including the IFT dynein-2 motor subunit gene DYNC2H1. Genetic heterogeneity and the large DYNC2H1 gene size have hindered JATD genetic diagnosis.

Genetics of early miscarriage.

A miscarriage is the most frequent complication of a pregnancy. Poor chromosome preparations, culture failure, or maternal cell contamination may hamper conventional karyotyping. Techniques such as chromosomal comparative genomic hybridization (chromosomal-CGH), array-comparative genomic hybridization (array-CGH), fluorescence in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA) and quantitative fluorescent polymerase chain reaction (QF-PCR) enable us to trace submicroscopic abnormalities.

Further delineation of CANT1 phenotypic spectrum and demonstration of its role in proteoglycan synthesis.

Desbuquois dysplasia (DD) is characterized by antenatal and postnatal short stature, multiple dislocations, and advanced carpal ossification. Two forms have been distinguished on the basis of the presence (type 1) or the absence (type 2) of characteristic hand anomalies. We have identified mutations in calcium activated nucleotidase 1 gene (CANT1) in DD type 1.

[The joys and burdens within clinical genetics--paternal discrepancy causes dilemmas].

We present three cases, a 25-year-old woman, a 52-year-old man and a 45-year-old woman, in whom paternal discrepancy (PD) adversely influenced genetic counselling. PD, with an estimated prevalence between 2% and 3%, occurs when a child is identified as being biologically fathered by someone other than the man who believes he is the father. The discovery of PD during genetic testing can cause health problems and psychosocial damage, and can increase costs, as illustrated by our three cases.