Prenatal Diagnosis Testing Research Articles

Cost-effectiveness of exome sequencing and chromosomal microarray for low-risk pregnancies

ObjectiveTo investigate the cost -effectiveness of exome and genome sequencing (ES), compared to Chromosomal microarray (CMA) Methodscosts, utility and quality adjusted life years (QALYs) were modeled for prenatal testing with CMA or CMA+ES. Average costs and utilities were discounted at 3%. Two strategies for screening were compared using Markovian decision analysis model: (1) CMA only- abnormal result culminating in termination of pregnancy and normal test has with 1/160 chance for severe disorders. (2) ES after a normal CMA, for positive result a termination of pregnancy (TOP) was conducted. One - way sensitivity analysis for all variables. Outcome measures included the QALYs after abortion, cost of CMA and ES test and the health expenses of a critically ill infant. The time horizon of the model was 20 years. ResultsTotal costs were $1,348 and $3,108 for CMA and CMA+ES strategies respectively. The QALYs with time horizon of 20 years were 14.15 and 14.19 QALYs for CMA and CMA+ES strategies respectively with incremental cost-effectiveness ratio (ICER) of 46,383$/QALYs. Sensitivity analysis revealed that the time horizon and the dis-utility of moderate/severe disability of the genetic disorder has an impact on the ICER. For example, with a relatively small disutility of moderate/sever disability, the ICER is 84,291$/QALYs and for a shorter time horizon of 10 years, the ICER is 94,148$/QALYs. ConclusionExome has the potential to be cost-effective compared with CMA alone. Our research provides data regarding the cost-effectiveness of ES without specific indication that will become increasingly important in the near future as whole exome sequencing becomes the first-tier test in prenatal diagnosis.

Reproductive options and genetic testing for patients with an inherited cardiac disease.

In the past decade, genetic testing for cardiac disease has become part of routine clinical care. A genetic diagnosis provides the possibility to clarify risk for relatives. For family planning, a genetic diagnosis provides reproductive options, including prenatal diagnosis and preimplantation genetic testing, that can prevent an affected parent from having a child with the genetic predisposition. Owing to the complex genetic architecture of cardiac diseases, characterized by incomplete disease penetrance and the interplay between monogenic and polygenic variants, the risk reduction that can be achieved using reproductive genetic testing varies among individuals. Globally, disparities, including regulatory and financial barriers, in access to reproductive genetic tests exist. Although reproductive options are gaining a prominent position in the management of patients with inherited cardiac diseases, specific policies and guidance are lacking. Guidelines recommend that prenatal diagnosis and preimplantation genetic testing are options that should be discussed with families. Health-care professionals should, therefore, be aware of the possibilities and feel confident to discuss the benefits and challenges. In this Review, we provide an overview of the reproductive options in the context of inherited cardiac diseases, covering the genetic, technical, psychosocial and equity considerations, to prepare health-care professionals for discussions with their patients.

Prenatal chromosomal microarray analysis in a large Chinese cohort of fetuses with congenital heart defects: a single center study

Background and objectivesCongenital heart defect (CHD) is one of the most common birth defects. The aim of this cohort study was to evaluate the prevalence of chromosomal abnormalities and the clinical utility of chromosomal microarray analysis (CMA) in fetuses with different types of CHD, aiming to assist genetic counseling and clinical decision-making.MethodsIn this study, 642 fetuses with CHD were enrolled from a single center over a six-year period (2017–2022). Both conventional karyotyping and CMA were performed simultaneously on these fetuses.ResultsThe diagnostic yield of CMA in fetuses with CHD in our study was 15.3% (98/642). Our findings revealed a significant increase in the diagnostic yield of CMA compared to karyotyping in fetuses with CHD. Among CHD subgroups, the diagnostic yields were high in complex CHD (34.9%), conotruncal defects (28.6%), right ventricular outflow tract obstructive defects (RVOTO) (25.9%), atrioventricular septal defects (AVSD) (25.0%) and left ventricular outflow tract obstructive defects (LVOTO) (24.1%), while those in other CHD (10.6%) and septal defects (10.9%) were relatively low. The overall detection rate of clinically significant chromosomal abnormalities was significantly higher in the non-isolated CHD group compared to the isolated CHD group (33.1% vs. 9.9%, P < 0.0001). Interestingly, numerical chromosomal abnormalities were more likely to occur in the non-isolated CHD group than in the isolated CHD group (20.3% vs. 2.0%, P < 0.0001). The rate of termination of pregnancy (TOP)/Still birth in the non-isolated CHD group was significantly higher than that in the isolated CHD group (40.5% vs. 20.6%, P < 0.0001). Compared to the isolated CHD group, the detection rate of clinically significant chromosomal abnormalities was significantly higher in the group of CHD with soft markers (35.6% vs. 9.9%, P < 0.0001) and in the group of CHD with additional structural anomalies (36.1% vs. 9.9%, P < 0.0001).ConclusionsCMA is a reliable and high-resolution technique that should be recommended as the front-line test for prenatal diagnosis of fetuses with CHD. The prevalence of chromosomal abnormalities varies greatly among different subgroups of CHD, and special attention should be given to prenatal non-isolated cases of CHD, especially those accompanied by additional structural anomalies or soft markers.

Multisite Evaluation and Validation of Optical Genome Mapping for Prenatal Genetic Testing

Prenatal diagnostic testing of amniotic fluid, chorionic villi, or more rarely, fetal cord blood is recommended following a positive or unreportable noninvasive cell-free fetal DNA test, abnormal maternal biochemical serum screen, abnormal ultrasound, or increased genetic risk for a cytogenomic abnormality based on family history. Although chromosomal microarray is recommended as the first-tier prenatal diagnostic test, in practice, multiple assays are often assessed in concert to achieve a final diagnostic result. The use of multiple methodologies is costly, time consuming, and labor intensive. Optical genome mapping (OGM) is an emerging technique with application for prenatal diagnosis because of its ability to detect and resolve, in a single assay, all classes of pathogenic cytogenomic aberrations. In an effort to characterize the potential of OGM as a novel alternative to traditional standard of care (SOC) testing of prenatal samples, OGM was performed on a total of 200 samples representing 123 unique cases, which were previously tested with SOC methods (92/123=74.7% cases tested with at least two SOCs). OGM demonstrated an overall accuracy of 99.6% when compared with SOC methods, a positive predictive value of 100%, and 100% reproducibility between sites, operators, and instruments. The standardized workflow, cost-effectiveness, and high-resolution cytogenomic analysis demonstrate the potential of OGM to serve as a first-tier test for prenatal diagnosis.

Case Report of Recurrent Popliteal Pterygium Syndrome

AbstractA 23 week pregnant woman with a history of a child with facial and limb malformations underwent a fetal ultrasound revealing similar abnormalities in the current fetus. Genetic testing confirmed a new IRF6 gene mutation consistent with popliteal pterygium syndrome type 1. This case highlights the potential for recurrence and the role of genetic testing in prenatal diagnosis.

Prospective Investigation of Optical Genome Mapping for Prenatal Genetic Diagnosis.

Optical genome mapping (OGM) is a novel assay for detecting structural variants (SVs) and has been retrospectively evaluated for its performance. However, its prospective evaluation in prenatal diagnosis remains unreported. This study aimed to prospectively assess the technical concordance of OGM with standard of care (SOC) testing in prenatal diagnosis. A prospective cohort of 204 pregnant women was enrolled in this study. Amniotic fluid samples from these women were subjected to OGM and SOC testing, which included chromosomal microarray analysis (CMA) and karyotyping (KT) in parallel. The diagnostic yield of OGM was evaluated, and the technical concordance between OGM and SOC testing was assessed. OGM successfully analyzed 204 cultured amniocyte samples, even with a cell count as low as 0.24 million. In total, 60 reportable SVs were identified through combined OGM and SOC testing, with 22 SVs detected by all 3 techniques. The diagnostic yield for OGM, CMA, and KT was 25% (51/204), 22.06% (45/204), and 18.14% (37/204), respectively. The highest diagnostic yield (29.41%, 60/204) was achieved when OGM and KT were used together. OGM demonstrated a concordance of 95.56% with CMA and 75.68% with KT in this cohort study. Our findings suggest that OGM can be effectively applied in prenatal diagnosis using cultured amniocytes and exhibits high concordance with SOC testing. The combined use of OGM and KT appears to yield the most promising diagnostic outcomes.

Variant analysis and prenatal diagnosis for two Chinese pedigrees affected with Spinal muscular atrophy with respiratory distress type 1

To explore the genetic etiology of two children with Spinal muscular atrophy with respiratory distress type 1 (SMARD1), and prevent the recurrence of birth defects. Two unrelated families who had visited the Obstetrics and Gynecology Medical Center of Drum Tower Hospital from August to November 2021 were selected as the study subjects. Copy number of SMN1 gene exon 7 for the probands and their parents was detected by multiple ligation-dependent probe amplification (MLPA). and whole exome sequencing (WES) was carried out to screen the variants in the probands. Sanger sequencing was used to validate the variants within the families. Pathogenicity of the variants were predicted by bioinformatic analysis. Based on the results, prenatal diagnosis was performed for the fetuses. Both probands were found to harbor compound heterozygous variants of the IGHMBP2 gene, which were inherited from their parents. Among these, c.1144C>T, c.866delG and c.1666C>G were previously unreported and respectively classified as pathogenic variant (PVS1+PM2_Supporting+PP3+PP4), likely pathogenic variant (PM1+PM2_Supporting+PM4+PP3+PP4) and likely pathogenic variant (PM1+PM2_Supporting+PP2+PP3+PP4) based on the ACMG guidelines. Through preimplantation genetic testing for monogenic (PGT-M) and interventional prenatal diagnosis, transmission of the variants within the families was successfully blocked. The SMARD1 in both children may be attributed to the compound heterozygous variants of the IGHMBP2 gene, which has facilitated the genetic diagnosis and counselling, and provided reference for delineating the molecular pathogenesis of this disease.

Single-tube multiplex real-time PCR with EvaGreen and high-resolution melting analysis for diagnosis of α0-thalassemia--SEA,--THAI, and--CR type deletions.

Regions with a high prevalence of α-thalassemia (α-thal) require simple, rapid, and accurate tests for carrier screening and prenatal diagnosis. Diagnosis of multiple deletions in a single tube is necessary to clearly identify individuals with α0-thalassemia in the routine setting, especially in at-risk couples. Therefore, we aimed to develop a single-tube multiplex real-time PCR with EvaGreen and high-resolution melting (HRM) analysis for the identification of α0-thalassemia Southeast Asian (SEA), Thai and Chiang Rai (CR) type deletions. The results of the HRM analysis indicated that the amplified fragments from α0-thal--CR,--THAI,--SEA, and the wild-type α-globin gene had specific peak heights at mean melting temperature (Tm) values of 85.40°C, 86.50°C, 87.65°C, and 91.04°C, respectively. The frequencies of α0-thal--SEA,--THAI,--CR obtained from routine testing in 2,135 samples were 17.89%, 0.19% and 0.19%, respectively. This method would be useful for preventing Hb Bart's hydrops fetalis. Detection of multiple deletions in a single run is cost-effective, highly accurate and timesaving. This technique could enable wider α-thalassemia diagnosis in high prevalence areas and served as an example for thalassemia routine setting.

Reasons for declining prenatal diagnostic tests and analysis of factors impacting the decision

Abstract&#x0D; Objective: To identify the factors impacting the decision of declining to have prenatal diagnostic tests and to determine the reasons for declining in cases with high trisomy risk in prenatal screening tests and those who refuse to undergo prenatal diagnostic tests.&#x0D; Materials and methods: Cases with positive test results in first and second trimester aneuploidy screening tests were included in the study. The patients were divided into two groups those who accepted prenatal diagnostic tests (Group 1) and those who refused prenatal diagnostic tests (Group 2). The patients that refused prenatal diagnostic tests were evaluated with a questionnaire to determine the reasons for refusal.&#x0D; Results: 204 cases were included in the study. 44 (21.6%) of these cases wanted to have prenatal diagnostic tests, while 160 (78.4%) refused to have prenatal diagnosis tests. A significant correlation was found between the decision to refuse the prenatal diagnostic test and the mother's educational status level (p=0.035), whereas no significant correlation was found between the personalized risk ratios and the number of abortions in previous pregnancies. Among the reasons for refusal of prenatal diagnosis test, the main reason was determined to be "Termination of pregnancy is not an option".&#x0D; Conclusion: Pregnant women should be offered all options, including not having a prenatal screening test or a prenatal diagnostic test, by providing accurate and understandable information about the purpose and potential outcomes of prenatal screening tests. Hence, pregnant women can be provided with the opportunity to make an informed choice.

Prenatal screening tests and prevalence of fetal aneuploidies in a tertiary hospital in Thailand.

This study evaluated prenatal screening test performance and the prevalence of common aneuploidies at Siriraj Hospital, Thailand. We collected data from screening tests which are first-trimester test, quadruple test, and noninvasive prenatal tests (NIPT) between January 2016 and December 2020. Thirty percent (7,860/25,736) of pregnancies received prenatal screening tests for aneuploidies disorders, and 17.8% underwent prenatal diagnosis tests without screening. The highest percentage of screening tests was first-trimester test (64.5%). The high-risk results were 4% for first-trimester test, 6.6% for quadruple test, and 1.3% for NIPT. The serum screening tests for trisomy 13 and 18 had no true positives; therefore, we could not calculate sensitivity. For the first-trimester test, the sensitivity for trisomy 21 was 71.4% (95% confidence intervals (CI) 30.3-94.9); specificity for trisomy 13 and 18 was 99.9% (95% CI 99.8-99.9); and for trisomy 21 was 96.1% (95% CI 95.6-96.7). For the quadruple test, the specificity for trisomy 18 was 99.6% (95% CI 98.9-99.8), while the sensitivity and specificity for trisomy 21 were 50% (95% CI 26.7-97.3) and 93.9% (95% CI 92.2-95.3), respectively. NIPT had 100% sensitivity and specificity for trisomy 13, 18 and 21, and there were neither false negatives nor false positives. For pregnant women < 35 years, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.28 (95% CI 0.12-0.67), 0.28 (95% CI 0.12-0.67), and 0.89 (95% CI 0.54-1.45), respectively. For pregnant women ≥35 years, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.26 (95% CI 0.06-1.03), 2.59 (95% CI 1.67-4.01), and 7.25 (95% CI 5.58-9.41), respectively. For all pregnancies, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.27 (95% CI 0.13-0.57), 0.97 (95% CI 0.66-1.44), 2.80 (95% CI 2.22-3.52), respectively.

Practical Applications of Chromosomal Microarray in Prenatal Diagnosis

AbstractG-banded karyotyping is the most common approach for the detection of genomic alterations. However, this is unable to detect genomic changes of less than 5 Mb. The ability of fluorescence in situ hybridization (FISH) to detect cryptic chromosomal rearrangements exceeds the resolution of routine karyotype. However, conventional FISH is for targeted regions only, whereas the chromosomal microarray is a whole-genome copy number evaluation technique with a resolution of 10 to 20 kb. In this article, we discuss the application of chromosomal microarray 750 K to 384 consecutive prenatal diagnosis cases. Overall diagnostic yield is 15.36%, and chromosomal microarray accounts for a 3.6% additional detection rate. We suggest applying this technique in routine prenatal diagnosis as a first-tier test in prenatal diagnosis along with a backup culture in all cases.

Prenatal karyotype results from 2169 invasive tests.

Foetal karyotyping is a basic tool used to diagnose the most common genetic syndromes. Although new molecular methods such as FISH, MLPA or QF-PCR allow rapid prenatal testing, they are of limited value when diagnosing less frequent chromosomal abnormalities. Chromosomal microarray analysis offers higher test resolution than traditional karyotyping and has been recommended as first-line genetic testing in prenatal diagnosis. The aim of the study was to confirm whether foetal karyotyping remains a valid approach to prenatal diagnosis by analysing its performance in a large population of pregnant women with a high risk of chromosomal aberration. An analysis was performed of 2169 foetal karyotypes from two referral university centres for prenatal diagnostics in Lodz, Poland. Amniocentesis and foetal karyotyping were performed when screening methods had indicated a high risk of chromosomal aberration, or when prenatal ultrasound had proved foetal abnormality. The study group included 205 (9.4%) abnormal foetal karyotypes. Rare aberrations were observed in 34 cases (e.g., translocations, inversions, deletions and duplication). A marker chromosome was present in five cases. One third of the chromosomal abnormalities observed in the prenatal tests were rarer aberrations (i.e., not trisomy 21, 18 or 13). As many of these could not be detected by the new molecular methods, foetal karyotyping remains an important component of prenatal diagnosis.

Genetic analysis of a case of mild epilepsy due to variant of SCN9A gene

To explore the genetic etiology of a patient with epilepsy and provide genetic counseling. A patient who had visited the Center for Reproductive Medicine of Shandong University on November 11, 2020 was selected as the study subject, and her clinic information was collected. Candidate variant was identified through whole exome sequencing (WES), and Sanger sequencing was used for validation. Possible transcriptional changes caused by the variant was detected by reverse transcription-PCR and Sanger sequencing. The patient was a 35-year-old female with no fever at the onset, loss of consciousness and abnormal firing in the temporal lobe, manifesting predominantly as convulsions and fainting. WES revealed that she had harbored a heterozygous c.2841+5G>A variant of the SCN9A gene, which was verified by Sanger sequencing. cDNA sequencing confirmed that 154 bases were inserted between exons 16 and 17 of the SCN9A gene, which probably produced a truncated protein and affected the normal function of the SCN9A protein. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.2841+5G>A variant was classified as likely pathogenic (PVS1_Strong+PM2_Supporting). The c.2841+5G>A variant of the SCN9A gene probably underlay the epilepsy in this patient. Above finding has enriched the variant spectrum of the SCN9A gene and provided a basis for the prenatal diagnosis and preimplantation genetic testing for this patient.

Single-cell whole-genome sequencing, haplotype analysis in prenatal diagnosis of monogenic diseases.

Monogenic inherited diseases are common causes of congenital disabilities, leading to severe economic and mental burdens on affected families. In our previous study, we demonstrated the validity of cell-based noninvasive prenatal testing (cbNIPT) in prenatal diagnosis by single-cell targeted sequencing. The present research further explored the feasibility of single-cell whole-genome sequencing (WGS) and haplotype analysis of various monogenic diseases with cbNIPT. Four families were recruited: one with inherited deafness, one with hemophilia, one with large vestibular aqueduct syndrome (LVAS), and one with no disease. Circulating trophoblast cells (cTBs) were obtained from maternal blood and analyzed by single-cell 15X WGS. Haplotype analysis showed that CFC178 (deafness family), CFC616 (hemophilia family), and CFC111 (LVAS family) inherited haplotypes from paternal and/or maternal pathogenic loci. Amniotic fluid or fetal villi samples from the deafness and hemophilia families confirmed these results. WGS performed better than targeted sequencing in genome coverage, allele dropout (ADO), and false-positive (FP) ratios. Our findings suggest that cbNIPT by WGS and haplotype analysis have great potential for use in prenatally diagnosing various monogenic diseases.

Economic evaluation of population-based, expanded reproductive carrier screening for genetic diseases in Australia

PurposeThis study aimed to evaluate the cost effectiveness of population-based, expanded reproductive carrier screening (RCS) for a 300 recessive gene panel from health service and societal perspectives. MethodsA microsimulation model (PreConMod) was developed using 2016 Australian Census data as the base population. Epidemiologic, health, and indirect cost data were based on literature review. The study assessed the incremental cost effectiveness ratio of expanded RCS compared with (1) no population screening and (2) 3-condition screening for cystic fibrosis, spinal muscular atrophy, and fragile X syndrome in a single birth cohort. Averted affected births and health service savings with expanded RCS were projected to year 2061. Both one-way and probability sensitivity analyses were conducted to assess the uncertainty of the parameter inputs. ResultsExpanded RCS was cost saving compared with no population screening and cost effective compared with the 3-condition screening (incremental cost effectiveness ratio of Australian dollar [AUD] 6287 per quality-adjusted life year gained) at an uptake rate of 50% for RCS, 59% for in vitro fertilization and preimplantation genetic testing, 90% for prenatal diagnosis testing, and 50% for elective termination of affected pregnancies and a cost of AUD595 per couple screened. Our model predicts that expanded RCS would avert one-third of affected births in a single birth cohort and reduce lifetime health service spending by AUD632.0 million. Expanded RCS was estimated to be cost saving from the societal perspective. ConclusionExpanded RCS is cost effective from health service and societal perspectives. Expanded RCS is projected to avert significantly more affected births and result in health service saving beyond those expected from 3-condition screening or no population screening.

Potential roles of extracellular vesicles as a noninvasive tool for prenatal genetic diagnosis

The rate of infertility is increasing owing to genetic and environmental factors. Consequently, assisted reproductive technology has been introduced as an alternative. Bearing in mind the global trend toward the transfer of only one embryo, there is an increasing trend for assessing embryo quality before transfer through prenatal genetic diagnosis (PGD) tests. This ensures that the best-quality embryos are implanted into the uterus. In the invitro fertilization cycle, PGD is not only used for diseases or quality checks before embryo freezing but also for evaluating unfortunate risks, such as aneuploidy, signs of early abortions, and preterm birth. However, traditional preimplantation genetic testing and screening approaches are invasive and harm the health of both the mother and embryo, raising the risk of miscarriage. In the last decade, embryonic extracellular vesicles (EVs) have been investigated and have emerged as a promising diagnostic tool. In this mini-review, we address the use of EVs as a noninvasive biomarker in PGD to test for biological hazards within the embryo without invading its cells. We summarize the state-of-the-art in the use of the embryo's EV content, genomic DNA, messenger RNA, and microRNA in the spent culture medium and their relationship with embryo quality, successful implantation, and pregnancy.

Novel homozygous silent mutation of ITGB3 gene caused Glanzmann thrombasthenia.

Glanzmann thrombasthenia (GT) is a rare inherited disease characterized by mucocutaneous bleeding due to the abnormalities in quantity or quality of platelet membrane GP IIb (CD41) or GP IIIa (CD61). GP IIb and GP IIIa are encoded by the ITGA2B and ITGB3 genes, respectively. Herein, we described a 7-year-old Chinese boy of the consanguineous couple who was diagnosed with GT based on the typical clinical manifestations, absence of blood clot retraction and the reduced expression of CD41 and CD61 in platelets. A homozygous silent variant c.1431C > T (p. G477=) of the ITGB3 gene was identified by the Whole-exome sequencing and confirmed by Sanger sequencing. The variant was predicted to affect the splicing. RT-PCR and sequencing revealed that the variant caused a deletion of 95 base pairs and frameshift, and subsequently created a premature stop codon in exon 10 of ITGB3 (p. G477Afs*30). It was indicated that the variant c.1431C > T (p. G477=) of ITGB3 was the cause for Glanzmann thrombasthenia. Our findings expanded the mutation spectrum and provided the information for the genetic counseling, prenatal diagnosis and preimplantation genetic testing (PGT).

Chapter 14 - Reproductive options in mitochondrial disease

Mitochondrial diseases require customized approaches for reproductive counseling, addressing differences in recurrence risks and reproductive options. The majority of mitochondrial diseases is caused by mutations in nuclear genes and segregate in a Mendelian way. Prenatal diagnosis (PND) or preimplantation genetic testing (PGT) are available to prevent the birth of another severely affected child. In at least 15%-25% of cases, mitochondrial diseases are caused by mitochondrial DNA (mtDNA) mutations, which can occur de novo (25%) or be maternally inherited. For de novo mtDNA mutations, the recurrence risk is low and PND can be offered for reassurance. For maternally inherited, heteroplasmic mtDNA mutations, the recurrence risk is often unpredictable, due to the mitochondrial bottleneck. PND for mtDNA mutations is technically possible, but often not applicable given limitations in predicting the phenotype. Another option for preventing the transmission of mtDNA diseases is PGT. Embryos with mutant load below the expression threshold are being transferred. Oocyte donation is another safe option to prevent the transmission of mtDNA disease to a future child for couples who reject PGT. Recently, mitochondrial replacement therapy (MRT) became available for clinical application as an alternative to prevent the transmission of heteroplasmic and homoplasmic mtDNA mutations.

The trends in early precision diagnosis and treatment strategies of multiple endocrine neoplasia type 2

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant hereditary neuroendocrine cancer syndrome characterized by medullary thyroid carcinoma, in combination or not with pheochromocytoma, hyperparathyroidism and extra-endocrine features, and two forms subtyped as MEN2A and MEN2B. Based on the correlation between RET proto-oncogene mutation and MEN2 phenotype, MEN2 could be prevented through prenatal diagnosis and preimplantation genetic testing. Integrating the detection of RET mutation with measurement of serum calcitonin, plasma or urinary metanephrine/normetanephrine, and serum parathyroid hormone levels could accurately predict the progression of MEN2, and then facilitating implementation of personalized precision treatment. In addition, increased awareness of MEN2 is needed, which requires participation of physicians, patients/family members, and relevant organizations, supplemented by psychological support, which could promote the comprehensive management of MEN2. The "5P" strategies for MEN2 represents a paradigm of precision medicine, which could effectively avoid or reduce the clinical adverse outcomes, improve the prognosis and quality of life of MEN2 patients.

How to choose a test for prenatal genetic diagnosis: a practical overview

Establishing the diagnosis of a fetal genetic disease in utero expands decision-making opportunities for individuals during pregnancy and enables providers to tailor prenatal care and surveillance to disease-specific risks. The selection of prenatal genetic tests is guided by key details from fetal imaging, family and obstetrical history, suspected diagnoses and mechanisms of disease, an accurate understanding of what abnormalities each test is designed to detect, and, at times, the gestational age at which testing is initiated. Pre- and posttest counseling, by or in conjunction with providers trained in genetics, ensure an accurate understanding of genetic tests, their potential results and limitations, estimated turnaround time for results, and the clinical implications of their findings. As prenatal diagnosis and testing options continue to expand rapidly, it is increasingly important for obstetrical providers to understand how to choose appropriate genetic testing and contextualize the clinical implications of their results.