Delving into the Role of lncRNAs in Papillary Thyroid Cancer: Upregulation of LINC00887 Promotes Cell Proliferation, Growth and Invasion.

Papillary thyroid carcinoma (PTC) is the most common histological category of thyroid cancer. In recent years, there has been an increasing number of studies on lncRNAs in PTC. Long intergenic non-protein coding RNA 887 (LINC00887) is a critical oncogene in developing other cancers. LINC00887 is upregulated in PTC samples but its role in PTC is currently unclear. This study aimed to investigate the impact the disruption of LINC00887 expression has on PTC progression. We performed a CRISPR/Cas9 strategy for the truncation of LINC00887 in BCPAP and TPC1 cell lines. Functional assays showed that LINC00887 knockdown in both TPC1 and BCPAP cells reduced cell proliferation, colony formation and migration, delayed the cell cycle, and increased apoptosis. These results strengthened the role of LINC00887 in cancer and showed for the first time that this lncRNA could be a potential oncogene in PTC, acting as a tumor promoter. Modulation of the immune system may be one of the etiopathogenic mechanisms of LINC00887 in PTC, as shown by the observed influence of this lncRNA on PD-L1 expression. In addition, the biological pathways of LINC00887 identified to date, such as EMT, the Wnt/ß-catenin signaling pathway or the FRMD6-Hippo signaling pathway may also be relevant regulatory mechanisms operating in PTC.

Long-Term Neurodevelopmental Outcome After Selective Fetoscopic Laser Therapy for Stage I Twin-Twin Transfusion Syndrome.

Twin-twin transfusion syndrome (TTTS) is a serious complication in monochorionic (MC) pregnancies. Fetoscopic laser surgery (FLS) is the primary treatment for advanced TTTS, but managing Quintero stage I TTTS is still controversial. We conducted an observational study evaluating the 2-year neurodevelopment of fetuses, which underwent FLS for stage I TTTS, compared with advanced TTTS and uncomplicated monochorionic diamniotic twins (MCDTs). The study included 156 children: 14 in stage I TTTS group, 28 in advanced TTTS group, and 114 in uncomplicated twin group. In stage I TTTS, 92.9% showed normal neurodevelopment, with no severe neurological impairments observed. These results were comparable with uncomplicated twins (92.1% normal neurodevelopment, P = .921, adjusted odds ratio [aOR] = 1.56, 95% confidence interval [CI] = 0.42-5.79; 1.8% severe impairment, P = .617). Advanced TTTS had a non-significant lower rate of normal neurodevelopment (89.3%, P = .710, aOR = 1.31, 95% CI = 0.12-14.87). In conclusion, FLS for stage I TTTS shows favorable long-term neurodevelopmental outcomes, similar to uncomplicated MC pregnancies.

Maternal and obstetric outcomes after Ex-Utero Intrapartum Treatment (EXIT): a single center experience.

BACKGROUND: The Ex-utero Intrapartum Treatment (EXIT) is a procedure developed to manage a range of fetal conditions, aiming to ensure the maintenance of neonatal airway and preserving the feto-placental circulation. Its goal is to enhance the neonatal ability to successfully transition and adapt to postnatal life, thereby reducing perinatal morbidity and mortality. However, EXIT has been associated with a high risk of maternal complications. This paper provides an overview of the indications and characteristics of the EXIT procedure, as well as the obstetric outcomes and maternal complications. METHODS: A retrospective analysis was conducted on a cohort of patients undergoing EXIT at our center between January 2007 and December 2022. Maternal outcomes, including demographic information, data related to the surgical procedure, surgical complications, and postoperative complications were analyzed. To assess the severity of the surgical complications, a modified Clavien-Dindo classification was used. Comparative analysis was performed by randomly selecting a sample from elective cesarean deliveries performed at our center. RESULTS: A total of 34 EXIT procedures were performed. According to the modified Clavien-Dindo classification, we observed no major complications, while minor maternal complications were present in 2.94% of cases. Compared to elective cesarean deliveries (n = 350), there were no significant differences in terms of maternal complications, highlighting the similarity observed in the mean decrease in postoperative hemoglobin (1.15 g/dL in EXIT vs. 1.2 g/dL in elective cesarean deliveries, p = 0.94). In EXIT group, there was a higher rate of polyhydramnios (26.47% vs 6.59%, p < 0.001), as well as the need for amnioreduction (14.71% vs 0%, p = 0.001) and preterm delivery (32.35% vs 6.02%, p = 0.001). There were no cases of endometritis, post-procedural fever, or abruptio placentae following EXIT. CONCLUSIONS: EXIT can be considered a safe procedure when performed under adequate conditions, including appropriate uterine access and proper anesthetic management. In our series, EXIT procedure was not associated with a higher incidence of maternal complications when compared to elective cesarean delivery. TRIAL REGISTRATION: Retrospectively registered.

Maternal and Neonatal Outcomes After Ex-Utero Intrapartum Treatment for Congenital Diaphragmatic Hernia: A Case Series.

INTRODUCTION: Despite advances in neonatal intensive care, fetuses with congenital diaphragmatic hernia (CDH) remain to have a poor prognosis. Exclusive postnatal treatment is inadequate in patients with moderate CDH (observed than expected lung-to-head ratio [O/E LHR] 26-45%) and can lead to respiratory failure at birth, requiring extracorporeal membrane oxygenation in 75% of cases. An ex-utero intrapartum treatment (EXIT) procedure may be beneficial in these cases, improving the fetal-neonatal transition. MATERIAL AND METHODS: We review all pregnancies with fetal isolated left CDH with moderate O/E LHR delivered by EXIT in our center from January 2007 to December 2022. Maternal and neonatal variables were analyzed. As primary outcomes, we included neonatal survival and mortality rates, surgical and infectious complications, uterine scar dehiscence, and blood loss during EXIT. As secondary outcomes, we studied recurrences of the diaphragmatic defect, long-term evolution, subsequent pregnancies, and mode of delivery. RESULTS: A total of 14 patients were delivered by the EXIT procedure, with a neonatal survival rate of 85.7%. All these children had optimal physical and neurocognitive development and no pulmonary morbidity. We found no major complications and 7.1% of minor maternal complications. There were no cases of surgical wound infection or endometritis. The median decrease in hemoglobin during the EXIT procedure was 1.9 mg/dL, and only one case required postoperative transfusion. Two out of the 14 women became pregnant again, and both pregnancies were uneventful. CONCLUSIONS: In our series, the EXIT procedure allows for adequate airway management associated with a high neonatal survival rate in patients with moderate O/E LHR CDH, with a low rate of neonatal and maternal complications.

Two Year Neurodevelopmental Outcome after Fetoscopic Laser Therapy for Twin-Twin Transfusion Syndrome: Comparison with Uncomplicated Monochorionic Diamniotic Twins.

BACKGROUND: Twin-twin Transfusion Syndrome (TTTS) represents a significant complication in monochorionic twin pregnancies, caused by an unbalanced shunting of blood through intertwin placental vascular anastomoses. Despite advances in fetoscopic laser surgery, TTTS is still associated with a high rate of cerebral injury. However, there are no studies comparing these pregnancies with uncomplicated monochorionic diamniotic (MCDA) twin pregnancies, establishing the baseline risk of neurodevelopmental impairment. The aim of this study is to evaluate the odds of neurodevelopmental impairment in MCDA twins who undergo fetoscopic laser surgery for twin-twin transfusion syndrome, in comparison to a cohort of uncomplicated MCDA twin pregnancies. STUDY DESIGN: This is a retrospective cohort study of children born from MCDA twin pregnancies at a single center between 2008 and 2019. A routine, standardized follow-up assessment was conducted at a minimum of 2 years after delivery. The primary outcome of this was a 2 year neurodevelopmental impairment. Neurological, motor, and cognitive development was assessed by using the revised Brunet-Lézine scale. RESULTS: 176 children met the enrolment criteria. Of these, 42 (24%; TTTS group) underwent fetoscopic laser surgery for TTTS during pregnancy, and 134 (76%; uncomplicated MCDA group) were uncomplicated MCDA pregnancies. The primary outcome was found in four children (9.52%) in the TTTS group and ten children (7.46%) in the uncomplicated MCDA group (p = 0.67, aOR 2.82, 95% CI 0.49-16.23). Major neurologic impairment was found in 2.38% after fetoscopic laser surgery and 1.49% in uncomplicated MCDA twins (p = 0.70, aOR 0.97, 95% CI 0.22-4.24). The data were adjusted by birth order, birth weight, and gestational age at birth. CONCLUSIONS: The outcome in MCDA twins who underwent fetoscopic laser surgery for TTTS is comparable to the outcome in uncomplicated MCDA twins. Our findings emphasize the need for long-term neurodevelopmental follow-ups in all children from monochorionic twin gestations.

Identification of Novel Candidate Genes for Familial Thyroid Cancer by Whole Exome Sequencing.

Thyroid carcinoma (TC) can be classified as medullary (MTC) and non-medullary (NMTC). While most TCs are sporadic, familial forms of MTC and NMTC also exist (less than 1% and 3-9% of all TC cases, respectively). Germline mutations in RET are found in more than 95% of familial MTC, whereas familial NMTC shows a high degree of genetic heterogeneity. Herein, we aimed to identify susceptibility genes for familial NMTC and non-RET MTC by whole exome sequencing in 58 individuals belonging to 18 Spanish families with these carcinomas. After data analysis, 53 rare candidate segregating variants were identified in 12 of the families, 7 of them located in previously TC-associated genes. Although no common mutated genes were detected, biological processes regulating functions such as cell proliferation, differentiation, survival and adhesion were enriched. The reported functions of the identified genes together with pathogenicity and structural predictions, reinforced the candidacy of 36 of them, suggesting new loci related to TC and novel genotype-phenotype correlations. Therefore, our strategy provides clues to possible molecular mechanisms underlying familial forms of MTC and NMTC. These new molecular findings and clinical data of patients may be helpful for the early detection, development of tailored therapies and optimizing patient management.

A comprehensive WGS-based pipeline for the identification of new candidate genes in inherited retinal dystrophies.

To enhance the use of Whole Genome Sequencing (WGS) in clinical practice, it is still necessary to standardize data analysis pipelines. Herein, we aimed to define a WGS-based algorithm for the accurate interpretation of variants in inherited retinal dystrophies (IRD). This study comprised 429 phenotyped individuals divided into three cohorts. A comparison of 14 pathogenicity predictors, and the re-definition of its cutoffs, were performed using panel-sequencing curated data from 209 genetically diagnosed individuals with IRD (training cohort). The optimal tool combinations, previously validated in 50 additional IRD individuals, were also tested in patients with hereditary cancer (n = 109), and with neurological diseases (n = 47) to evaluate the translational value of this approach (validation cohort). Then, our workflow was applied for the WGS-data analysis of 14 individuals from genetically undiagnosed IRD families (discovery cohort). The statistical analysis showed that the optimal filtering combination included CADDv1.6, MAPP, Grantham, and SIFT tools. Our pipeline allowed the identification of one homozygous variant in the candidate gene CFAP20 (c.337 C > T; p.Arg113Trp), a conserved ciliary gene, which was abundantly expressed in human retina and was located in the photoreceptors layer. Although further studies are needed, we propose CFAP20 as a candidate gene for autosomal recessive retinitis pigmentosa. Moreover, we offer a translational strategy for accurate WGS-data prioritization, which is essential for the advancement of personalized medicine.

Mode of delivery, perinatal outcome and neurodevelopment in uncomplicated monochorionic diamniotic twins: a single-center retrospective cohort study.

BACKGROUND: There is no agreement on the effect of planned mode of delivery in the perinatal morbidity and neurodevelopment in uncomplicated monochorionic diamniotic as well as regarding the safest mode of delivery. In this paper we have aimed to analyze the impact of the mode of delivery in uncomplicated monochorionic diamniotic twins ≥ 32 weeks of gestation. MATERIAL AND METHODS: This study included 72 women, followed and attended at our department, with uncomplicated monochorionic diamniotic pregnancies who had a birth between 32.0 and 37.6 weeks of gestation from January 2012 to December 2018. Outcomes were recorded in women who underwent planned vaginal delivery (induced or spontaneous onset of labor), and women who underwent a planned cesarean section for any reason that excluded vaginal delivery. Primary outcomes included: (1) A composite of any of the following: neonatal death, 5-min Apgar score < 4, respiratory distress syndrome, bronchopulmonary dysplasia, sepsis, periventricular leukomalacia, intraventricular hemorrhage, and necrotizing enterocolitis. (2) Neurodevelopmental status at 2 years of corrected age. RESULTS: In this period, 42 women (58.3%) had a planned vaginal delivery, and 30 women (41.7%) had a planned cesarean section. In the first group, 64.3% had a vaginal delivery. The rate of successful vaginal delivery was similar regardless the onset of labor. We did not find a higher composite perinatal morbidity in the planned vaginal delivery group (planned vaginal delivery: 3.6% vs. planned cesarean section: 8.3%, aOR 1.36, 95% CI 0.24-7.81). Considering the onset of labor, it was more frequent in the spontaneous subgroup (8.3% vs. 0%). The rate of neurodevelopmental impairment was higher in the planned cesarean section group, without reaching statistical significance [10.2% vs. 4.9%, aOR 1.53 (95% CI 0.37-6.29)]. CONCLUSIONS: In uncomplicated monochorionic diamniotic twins at ≥ 32 weeks of gestation, when the first twin is in vertex presentation, our results suggest that planned vaginal delivery is safe, with a successful outcome as well as high vaginal delivery rate.

Unusual clinical phenotype of Stargardt disease / Fenótipo clínico incomum da doença de Stargardt

ABSTRACT Mutations in the ABCA4 gene are a common cause of Stargardt disease; however, other retinal phenotypes have also been associated with mutations in this gene. We describe an observational case report of an unusual clinical phenotype of Stargardt disease. The ophthalmological examination included best corrected visual acuity, color and autofluorescence photography, fluorescein angiography, optical coherence tomography, and electrophysiology tests. Targeted next-generation sequencing of 99 genes associated with inherited retinal dystrophies was performed in the index patient. A 48-year-old woman presented with a best corrected visual acuity of 20/25 and 20/20. Fundoscopy revealed perifoveal yellow flecked-like lesions. Fluorescein angiography and fundus autofluorescence findings were consistent with pattern dystrophy. Pattern electroretinogram demonstrated bilateral decrease of p50 values. Genetic testing identified two heterozygous missense mutations, c.428C>T, p.(Pro143Leu) and c.3113C>T, p.(Ala.1038Val), in the ABCA4 gene. Based on our results, we believe that these particular mutations in the ABCA4 gene could be associated with a specific disease phenotype characterized by funduscopic appearance similar to pattern dystrophy. A detailed characterization of the retinal phenotype in patients carrying specific mutations in ABCA4 is crucial to understand disease expression and ensure optimal clinical care for patients with inherited retinal dystrophies.

RESUMO Mutações no gene ABCA4 são causa comum da doença de Stargardt, mas outros fenótipos da retina também foram associados a mutações nesse gene. Apresentamos um relato de caso observacional de um fenótipo clínico incomum da doença de Stargardt. O exame oftalmológico incluiu a acuidade visual com melhor correção, fotografia em cores e com autofluorescência, angiofluoresceinografia, tomografia de coerência óptica e testes de eletrofisiologia. Na paciente em questão, realizou-se o sequenciamento de próxima geração de 99 genes associados a distrofias retinais hereditárias. Tratava-se de uma mulher de 48 anos com melhor acuidade visual corrigida de 20/25 e 20/20. A fundoscopia revelou lesões puntiformes amarelas perifoveais. Os resultados da angiofluoresceinografia e da autofluorescência do fundo de olho foram consistentes com distrofia em padrão. A eletrorretinografia por padrões mostrou diminuição bilateral dos valores de p50. Os testes genéticos revelaram duas mutações missense heterozigóticas, c.428C>T, p. (Pro143Leu) e c.3113C>T, p. (Ala.1038Val), no gene ABCA4. Nossos resultados nos fazem pensar que essas mutações específicas em ABCA4 talvez possam estar associadas a um fenótipo específico da doença, caracterizado por uma aparência fundoscópica semelhante à da distrofia em padrão. Uma caracterização detalhada do fenótipo da retina em pacientes portadores de mutações específicas em ABCA4 é crucial para compreender a expressão da doença e para garantir o tratamento clínico ideal para pacientes com distrofias retinais hereditárias.

RMRP, RMST, FTX and IPW: novel potential long non-coding RNAs in medullary thyroid cancer.

The relevant role of long non-coding RNAs (lncRNAs) in cancer is currently a matter of increasing interest. Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor (2-5% of all thyroid cancer) derived from the parafollicular C-cells which secrete calcitonin. About 75% of all medullary thyroid cancers are believed to be sporadic medullary thyroid cancer (sMTC), whereas the remaining 25% correspond to inherited cancer syndromes known as Multiple Endocrine Neoplasia type 2 (MEN2). MEN2 syndrome, with autosomal dominant inheritance is caused by germline gain of function mutations in RET proto-oncogene. To date no lncRNA has been associated to MEN2 syndrome and only two articles have been published relating long non-coding RNA (lncRNA) to MTC: the first one linked MALAT1 with sMTC and, in the other, our group determined some new lncRNAs in a small group of sMTC cases in fresh tissue (RMST, FTX, IPW, PRNCR1, ADAMTS9-AS2 and RMRP). The aim of the current study is to validate such novel lncRNAs previously described by our group by using a larger cohort of patients, in order to discern their potential role in the disease. Here we have tested three up-regulated (RMST, FTX, IPW) and one down-regulated (RMRP) lncRNAs in our samples (formalin fixed paraffin embedded tissues from twenty-one MEN2 and ten sMTC patients) by RT-qPCR analysis. The preliminary results reinforce the potential role of RMST, FTX, IPW and RMRP in the pathogenesis of MTC.

Ex-Utero Intrapartum Treatment (EXIT): indications and outcome in fetal cervical and oropharyngeal masses.

BACKGROUND: The "Ex-Utero Intrapartum Treatment" (EXIT) procedure allows to ensure fetal airway before completion of delivery and umbilical cord clamping while keeping uteroplacental circulation. Airway obstruction in fetal oropharyngeal and cervical masses can be life-threatening at birth. In those situations, controlled access to fetal airway performed by a trained multidisciplinary team allows safe airway management, while feto-maternal circulation is preserved. We aim to review the indications and outcome of the EXIT procedure in a case series of fetal cervical and oropharyngeal masses. METHODS: We have carried out a retrospective review of all patients with fetal cervical and oropharyngeal masses who underwent an EXIT procedure between 2008 and 2019. Variables evaluated included indication for EXIT, ultrasound and MRI findings, the need of amnioreduction, gestational age at EXIT, birth weight, complications, operative time, survival rate, pathological findings, and postnatal evolution. Five patients are included in this series. One additional case has already been published. RESULTS: The diagnosis were cervical teratoma (n = 1), epulis (n = 1) and lymphangioma (n = 3). Polyhydramnios was present in 2 patients, requiring amnioreduction in one of them. Mean gestational age at EXIT was 36-37 weeks (range, 34-38 weeks). Median EXIT time in placental support was 9 min (range, 3-22 min). Access to airway was successfully established in EXIT in all cases. All children born by EXIT are currently healthy and without complications. CONCLUSION: The localization and characteristics of the mass, its relationship to the airway, and the presence of polyhydramnios seem to be major factors determining indications for EXIT and clinical outcome.

What is new about the genetic background of Hirschsprung disease?

Hirschsprung disease (HSCR) is a rare congenital disorder caused by an incorrect enteric nervous system development due to a failure in migration, proliferation, differentiation and/or survival of enteric neural crest cells. HSCR is a complex genetic disease, where alterations at different molecular levels are required for the manifestation of the disease. In addition, a wide spectrum of mutations affecting many different genes cause HSCR, although the occurrence and severity of HSCR from many cases still remain unexplained. This review summarizes the current knowledge about molecular genetic basis of HSCR.

Influencers on Thyroid Cancer Onset: Molecular Genetic Basis.

Thyroid cancer, a cancerous tumor or growth located within the thyroid gland, is the most common endocrine cancer. It is one of the few cancers whereby incidence rates have increased in recent years. It occurs in all age groups, from children through to seniors. Most studies are focused on dissecting its genetic basis, since our current knowledge of the genetic background of the different forms of thyroid cancer is far from complete, which poses a challenge for diagnosis and prognosis of the disease. In this review, we describe prevailing advances and update our understanding of the molecular genetics of thyroid cancer, focusing on the main genes related with the pathology, including the different noncoding RNAs associated with the disease.

Epigenetic Mechanisms in Hirschsprung Disease.

Hirschsprung disease (HSCR, OMIM 142623) is due to a failure of enteric precursor cells derived from neural crest (EPCs) to proliferate, migrate, survive or differentiate during Enteric Nervous System (ENS) formation. This is a complex process which requires a strict regulation that results in an ENS specific gene expression pattern. Alterations at this level lead to the onset of neurocristopathies such as HSCR. Gene expression is regulated by different mechanisms, such as DNA modifications (at the epigenetic level), transcriptional mechanisms (transcription factors, silencers, enhancers and repressors), postranscriptional mechanisms (3'UTR and ncRNA) and regulation of translation. All these mechanisms are finally implicated in cell signaling to determine the migration, proliferation, differentiation and survival processes for correct ENS development. In this review, we have performed an overview on the role of epigenetic mechanisms at transcriptional and posttranscriptional levels on these cellular events in neural crest cells (NCCs), ENS development, as well as in HSCR.

Expanding the clinical and mutational spectrum of germline ABL1 mutations-associated syndrome: A case report.

RATIONALE: Clinical and genetic management of patients with rare syndromes is often a difficult, confusing, and slow task. PATIENT CONCERNS: Male child patient with a multisystemic disease showing congenital heart defects, facial dysmorphism, skeletal malformations, and eye anomalies. DIAGNOSIS: The patient remained clinically undiagnosed until the genetic results were conclusive and allowed to associate its clinical features with the germline ABL1 mutations-associated syndrome. INTERVENTIONS: We performed whole-exome sequencing to uncover the underlying genetic defect in this patient. Subsequently, family segregation of identified mutations was performed by Sanger sequencing in all available family members. OUTCOMES: The only detected variant compatible with the disease was a novel heterozygous nonframeshift de novo deletion in ABL1 (c.434_436del; p.Ser145del). The affected residue lays in a functional domain of the protein, it is highly conserved among distinct species, and its loss is predicted as pathogenic by in silico studies. LESSONS: Our results reinforce the involvement of ABL1 in clinically undiagnosed cases with developmental defects and expand the clinical and genetic spectrum of the recently reported ABL1-associated syndrome. In this sense, we described the third germline ABL1 causative mutation and linked, for the first time, ocular anterior chamber anomalies to this pathology. Thus, we suggest that this disorder may be more heterogeneous than is currently believed and may be overlapping with other multisystemic diseases, hence genetic and clinical reassessment of this type of cases should be considered to ensure proper diagnosis.

Searching the second hit in patients with inherited retinal dystrophies and monoallelic variants in ABCA4, USH2A and CEP290 by whole-gene targeted sequencing.

Inherited Retinal Dystrophies are clinically and genetically heterogeneous disorders affecting the photoreceptors. Although NGS has shown to be helpful for the molecular diagnosis of these conditions, some cases remain unsolved. Among these, several individuals harboured monoallelic variants in a recessive gene, suggesting that a comprehensive screening could improve the overall diagnosis. In order to assess the contribution of non-coding variations in a cohort of 29 patients, 25 of them with monoallelic mutations, we performed targeted NGS. The design comprised the entire genomic sequence of three genes (USH2A, ABCA4 and CEP290), the coding exons of 76 genes and two disease-associated intronic regions in OFD1 and PRPF31. As a result, likely causative mutations (8 novel) were identified in 17 probands (diagnostic rate: 58.62%), including two copy-number variations in USH2A (one deletion of exons 22-55 and one duplication of exons 46-47). Possibly damaging deep-intronic mutations were identified in one family, and another with a monoallelic variant harboured causal mutations in a different locus. In conclusion, due to the high prevalence of carriers of IRD mutations and the results obtained here, sequencing entire genes do not seem to be the approach of choice for detecting the second hit in IRD patients with monoallelic variants.

Trans-ethnic meta-analysis of genome-wide association studies for Hirschsprung disease.

Hirschsprung disease (HSCR) is the most common cause of neonatal intestinal obstruction. It is characterized by the absence of ganglia in the nerve plexuses of the lower gastrointestinal tract. So far, three common disease-susceptibility variants at the RET, SEMA3 and NRG1 loci have been detected through genome-wide association studies (GWAS) in Europeans and Asians to understand its genetic etiologies. Here we present a trans-ethnic meta-analysis of 507 HSCR cases and 1191 controls, combining all published GWAS results on HSCR to fine-map these loci and narrow down the putatively causal variants to 99% credible sets. We also demonstrate that the effects of RET and NRG1 are universal across European and Asian ancestries. In contrast, we detected a European-specific association of a low-frequency variant, rs80227144, in SEMA3 [odds ratio (OR) = 5.2, P = 4.7 × 10-10]. Conditional analyses on the lead SNPs revealed a secondary association signal, corresponding to an Asian-specific, low-frequency missense variant encoding RET p.Asp489Asn (rs9282834, conditional OR = 20.3, conditional P = 4.1 × 10-14). When in trans with the RET intron 1 enhancer risk allele, rs9282834 increases the risk of HSCR from 1.1 to 26.7. Overall, our study provides further insights into the genetic architecture of HSCR and has profound implications for future study designs.

Derivation of HVR1, HVR2 and HVR3 human embryonic stem cell lines from IVF embryos after preimplantation genetic diagnosis (PGD) for monogenic disorder.

From 106 human blastocyts donate for research after in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for monogenetic disorder, 3 human embryonic stem cells (hESCs) HVR1, HVR2 and HVR3 were successfully derived. HVR1 was assumed to be genetically normal, HVR2 carrying Becker muscular dystrophy and HVR3 Hemophilia B. Despite the translocation t(9;15)(q34.3;q14) detected in HVR2, all the 3 cell lines were characterised in vitro and in vivo as normal hESCs lines and were registered in the Spanish Stem Cell Bank.