Clinical characteristics and survival of trisomy 13 in a medical center in Taiwan, 1985-2004

From genes to therapy: A comprehensive exploration of congenital heart disease through the lens of genetics and emerging technologies

Congenital heart disease (CHD) affects approximately 1 % of live births worldwide, making it the most common congenital anomaly in newborns. Recent advancements in genetics and genomics have significantly deepened our understanding of the genetics of CHDs. While the majority of CHD etiology remains unclear, evidence consistently indicates that genetics play a significant role in its development. CHD etiology holds promise for enhancing diagnosis and developing novel therapies to improve patient outcomes. In this review, we explore the contributions of both monogenic and polygenic factors of CHDs and highlight the transformative impact of emerging technologies on these fields. We also summarized the state-of-the-art techniques, including targeted next-generation sequencing (NGS), whole genome and whole exome sequencing (WGS, WES), single-cell RNA sequencing (scRNA-seq), human induced pluripotent stem cells (hiPSCs) and others, that have revolutionized our understanding of cardiovascular disease genetics both from diagnosis perspective and from disease mechanism perspective in children and young adults. These molecular diagnostic techniques have identified new genes and chromosomal regions involved in syndromic and non-syndromic CHD, enabling a more defined explanation of the underlying pathogenetic mechanisms. As our knowledge and technologies continue to evolve, they promise to enhance clinical outcomes and reduce the CHD burden worldwide.

Human Genetics of Congenital Heart Defects

Congenital heart diseases (or congenital heart defects/disorders; CHDs) are structural abnormalities of the heart and/or great vessels that are present at birth. CHDs include an extensive range of defects that may be minor and require no intervention or may be life-limiting and require complex surgery shortly after birth. This chapter reviews the current knowledge on the genetic causes of CHD.

[Congenital heart disease associated with the most prevalent chromosomal syndromes: a literature review]

Most frequent chromosomal syndromes like Down, Patau, Edwards, Turner, and Williams affect the pediatric population in various ways, and congenital heart disease explains the altered quality of life they suffer. There is a lack of studies reviewing the cardiac anomalies in these syndromes, and the ones that exist are publications from past decades. We reviewed databases such as MEDLINE, LILACS, SCIELO, and Google Scholar, selecting the best possible evidence, and each chromosomal syndrome was investigated in relation to congenital heart disease, constituting five search groups. The article shows the characteristics of each heart disease described in the studies reviewed, the author, date of publication, country, and population studied, as well as a brief description of the frequency of the disease and its mortality. The results described in this review were contrasted with previous existing literature to verify if there was correspondence between the reported frequencies. The most frequent congenital heart diseases were atrioventricular septal defect (AVSD), ventricular septal defect (VSD), atrial septal defect (ASD), and persistent ductus arteriosus (PDA) in Down syndrome patients, PDA, ASD, and VSD in Patau syndrome patients, AVSD, PDA and valvular defects in Edwards syndrome, bicuspid aortic valve, aortic coarctation and aortic stenosis in Turner syndrome, and supravalvular aortic stenosis and pulmonary stenosis in Williams syndrome.

Genetic Basis of Human Congenital Heart Disease

Congenital heart disease (CHD) is the most common major congenital anomaly with an incidence of ∼1% of live births and is a significant cause of birth defect-related mortality. The genetic mechanisms underlying the development of CHD are complex and remain incompletely understood. Known genetic causes include all classes of genetic variation including chromosomal aneuploidies, copy number variants, and rare and common single-nucleotide variants, which can be either de novo or inherited. Among patients with CHD, ∼8%-12% have a chromosomal abnormality or aneuploidy, between 3% and 25% have a copy number variation, and 3%-5% have a single-gene defect in an established CHD gene with higher likelihood of identifying a genetic cause in patients with nonisolated CHD. These genetic variants disrupt or alter genes that play an important role in normal cardiac development and in some cases have pleiotropic effects on other organs. This work reviews some of the most common genetic causes of CHD as well as what is currently known about the underlying mechanisms.

Congenital heart defects associated with aneuploidy syndromes: New insights into familiar associations

The frequent occurrence of congenital heart defects (CHDs) in chromosome abnormality syndromes is well-known, and among aneuploidy syndromes, distinctive patterns have been delineated. We update the type and frequency of CHDs in the aneuploidy syndromes involving trisomy 13, 18, 21, and 22, and in several sex chromosome abnormalities (Turner syndrome, trisomy X, Klinefelter syndrome, 47,XYY, and 48,XXYY). We also discuss the impact of noninvasive prenatal screening (mainly, cell-free DNA analysis), critical CHD screening, and the growth of parental advocacy on their surgical management and natural history. We encourage clinicians to view the cardiac diagnosis as a "phenotype" which supplements the external dysmorphology examination. When detected prenatally, severe CHDs may influence decision-making, and postnatally, they are often the major determinants of survival. This review should be useful to geneticists, cardiologists, neonatologists, perinatal specialists, other pediatric specialists, and general pediatricians. As patients survive (and thrive) into adulthood, internists and related adult specialists will also need to be informed about their natural history and management.

Duplicated distal phalanx of thumb or hallux in trisomy 13: A recurrent feature in a series of 42 fetuses

Trisomy 13 or Patau syndrome (PS) is a well-known aneuploidy characterized by a polymalformative syndrome. We described a large series of fetuses with PS and compared them with cases described in the literature, most of which were live-born. In all, 42 fetuses, aged from 14 to 41 gestational weeks (GW), were examined. The main defects observed were similar to those described in live-born patients: congenital heart defects (76%), holoprosencephaly spectrum anomalies including arhinencephaly and hypotelorism (74%), urinary tract anomalies (71%), ear anomalies (69%), postaxial polydactyly (67%), anogenital anomalies (60%), anophthalmos, and/or microphthalmos (53%), brachycephaly (45%), and oro-facial clefts (45%). A duplication or triplication of at least one distal phalanx of the thumb or hallux was present in 38% of fetuses. This sign has only been reported previously in one patient in the literature. Fetal examination in trisomy 13, is thus, useful to complete the phenotype or to orient diagnosis toward trisomy 13 in the absence of cytogenetic analysis.

Clinical courses of children with trisomy 13 receiving intensive neonatal and pediatric treatment

Management of children with trisomy 13 (T13) is controversial because of a paucity of evidence of the natural history, especially focusing on efficacy of treatment. There has been no report regarding natural history of children with T13 receiving intensive neonatal and pediatric treatment without cardiac surgery, although several reports have suggested efficacy of cardiac surgery. To describe the detailed and comprehensive natural history of children with T13 receiving intensive neonatal and pediatric treatment without cardiac surgery, we reviewed clinical information of 24 children with full T13 (15 boys, 9 girls) who were admitted to Nagano Children's Hospital from 1994 to 2016. Intensive neonatal and pediatric treatment without cardiac surgery was provided through careful discussion with the parents. We detailed accurate frequencies of complications, survival, underlying factors and the final modes of death, and psychomotor development of survivors. Unpublished complications including aortopulmonary window, pulmonary-ductus-descending aorta-trunk, biliary system abnormalities, eosinophilic enteritis, and neuroblastoma were described. Accurate frequencies of congenital heart defects (92%) and laryngomalacia and/or tracheomalacia (42%) were determined. The median survival time was 451 days and the 1-year survival rate was 54%. The major underlying factor associated with death was congenital heart defects and heart failure (63%) and the major final mode of death was heart failure (50%). Long-term survivors appeared to show slow but constant psychomotor development. Intensive neonatal and pediatric treatment without cardiac surgery for children with T13 is efficient for survival and psychomotor development, and could be a reasonable choice for parents having fetuses or children with T13.

Prenatal counseling and parental decision-making following a fetal diagnosis of trisomy 13 or 18

OBJECTIVES

To evaluate parental decisions following a prenatal diagnosis of trisomy 13 (T13) or trisomy 18 (T18), prenatal counseling received, and pregnancy outcomes.

STUDY DESIGN

Single-center, retrospective cohort study of families with a prenatal diagnosis of T13 or T18 from 2000 to 2016.

RESULTS

Out of 152 pregnancies, 55% were terminated. Twenty percent chose induction with palliative care, 20% chose expectant management, 2% chose full interventions, and 3% were lost to follow-up. Counseling was based on initial parental goals, but most women were given options besides termination. Women who chose expectant management had a live birth in 50% of the cases. Women who chose neonatal interventions had a live birth in 100% of the cases, but there were no long-term survivors.

CONCLUSIONS

The majority of women who continue their pregnancy after a fetal diagnosis of T13 or T18 desire expectant management with palliative care. A live birth can be expected at least half of the time.

Syndromes associated with holoprosencephaly

Holoprosencephaly (HPE) is partial or complete failure of the forebrain to divide into hemispheres and can be an isolated finding or associated with a syndrome. Most cases of HPE are associated with a syndrome and roughly 40%-60% of fetuses with HPE have trisomy 13 which is the most common etiology of HPE. Other syndromes associated with HPE include additional aneuploidies like trisomy 18 and single gene disorders such as Smith-Lemli-Opitz syndrome. There are a number of syndromes such as pseudotrisomy 13 which do not have a known molecular etiology; therefore, this review has two parts: syndromes with a molecular diagnosis and syndromes where the etiology is yet to be found. As most HPE is syndromic, this review provides a comprehensive list and description of syndromes associated with HPE that may be used as a differential diagnosis and starting point for evaluating individuals with HPE.

Major anomalies and birth-weight influence NICU interventions and mortality in infants with trisomy 13 or 18

OBJECTIVE

To describe neonatal intensive care unit (NICU) medical interventions and NICU mortality by birth weight and major anomaly types for infants with trisomy 13 (T13) or 18 (T18).

STUDY DESIGN

Retrospective cohort analysis of infants with T13 or T18 from 2005 to 2012 in the Pediatrix Medical Group. We classified infants into three groups by associated anomaly type: neonatal surgical, non-neonatal surgical and minor. Outcomes were NICU medical interventions and mortality.

RESULTS

841 infants were included from 186 NICUs. NICU mortality varied widely by anomaly type and birth weight, from 70% of infants <1500 g with neonatal surgical anomalies to 31% of infants ⩾2500 g with minor anomalies. Infants ⩾1500 g without a neonatal surgical anomaly comprised 66% of infants admitted to the NICU; they had the lowest rates of NICU medical interventions and NICU mortality.

CONCLUSIONS

Risk stratification by anomaly type and birth weight may help provide more accurate family counseling for infants with T13 and T18.

The outcomes of 31 cases of trisomy 13 diagnosed in utero with various management options

There are few reports on the prognosis of prenatally diagnosed trisomy 13 in relation to postnatal management. The aim of this study was to report on the prenatal and postnatal outcomes and postnatal management of trisomy 13 fetuses that were prenatally diagnosed at our center between 2003 and 2015. The data were retrospectively reviewed from medical records. Of the 31 cases of trisomy 13, 12 patients were diagnosed before 22 weeks of gestation, and 19 were diagnosed at or after 22 weeks of gestation. Nine families opted for termination of the pregnancy, 14 fetuses died, and 8 were born alive. Aggressive treatment was requested in two of the live births, with one patient achieving long-term survival (7 years). The other died during infancy (Day 61). One out of four who received palliative treatment is alive at two years of age with only nutrition supplementation. These three patients who achieved neonatal survival had few structural anomalies. Fetal death and early neonatal death are common in trisomy 13; however, fetuses that receive medical treatment for cases without major ultrasound abnormalities may achieve neonatal survival. Therefore, it is useful to provide comprehensive information, including precise ultrasound findings and treatment options, to parents with trisomy 13 fetuses during genetic counseling.

The Diagnostic Significance of Comorbidities of Congenital Heart Diseases, Low-Set Ears, and Intrauterine Growth Restriction in Neonates With Trisomies 13 and 18

Background

Objectives

Patients and Methods

Results

Conclusions

Oral health needs in individuals with trisomy 18 and trisomy 13: Implications for dental professionals

The purpose of this study was to examine oral health needs and dental care in individuals with trisomy 18 and trisomy 13 (full, mosaic, partial and other, mixed types). Primary feeding method was also examined. Data was collected from a parent-completed, mixed method survey (TRIS Survey). Mean age in months was 120.2 (range 38 to 394 months) and 133 (range 36 to 405 months), respectively, for trisomy 18 and trisomy 13 individuals. Results indicated the majority of individuals received routine dental care from their family dentist. Approximately 80% in both groups needed some form of specialized dental care. Close to 25% and 30% of trisomy 18 and trisomy 13 individuals, respectively, required hospital admission for specialized dental care. Responses indicated the presence of excessive plaque and tooth decay across the groups with a higher incidence for individuals with trisomy 13. Although not the primary form of intake, over half of the individuals received oral feedings. Implications for dental care and management are provided along with the need for additional research to confirm or disconfirm this study's findings.

Genetic polymorphisms of short tandem repeat loci D13S305, D13S631 and D13S634 in the Han population of Tianjin, China

Short tandem repeat (STR) markers, also known as microsatellites, are extensively used in mapping studies, forensics and disease diagnosis due to their small dimension and low mutation and high polymorphism rates. In recent years quantitative fluorescence polymerase chain reaction (QF-PCR) has been successfully used to amplify STR markers in the prenatal diagnosis of common chromosomal abnormalities. This method provides a diagnosis of common aneuploidies 24-48 h after sampling with low error rates and cost; however, the size of different alleles, frequency, heterozygosity and distribution of STR markers vary among different populations. In the present study three STR markers, D13S305, D13S631 and D13S634, on chromosome 13 were analyzed in 350 unrelated individuals (200 males and 150 females) from the Han population of Tianjin, China using QF-PCR. Eleven, seven and 11 alleles of each marker were observed, respectively. The frequencies of the genotypes were in good agreement with Hardy-Weinberg equilibrium (P>0.05). The results showed that these three STR markers were highly polymorphic in the Han population of Tianjin, China. The study has provided basic data for use in the prenatal diagnosis of Patau syndrome.

Preaxial polydactyly of the foot: variable expression of trisomy 13 in a case from central Africa

Trisomy 13 is a chromosomal disorder characterized by a severe clinical picture of multiple congenital anomalies. We here describe the clinical and genetic features and prognosis observed in a newborn with trisomy 13 from Central Africa. He presented the rare feature of preaxial polydactyly of the feet.

Gestational, perinatal and family findings of patients with Patau syndrome

OBJECTIVE

To describe gestational, perinatal and family findings of patients with Patau syndrome (PS).

METHODS

The study enrolled patients with PS consecutively evaluated during 38 years in a Clinical Genetics Service of a pediatric referral hospital in Southern Brazil. The clinical data and the results of cytogenetic analysis were collected from the medical records. For statistical analysis, the two-tailed Fisher's exact test and the chi-square test with Yates' correction were used, being significant p<0.05.

RESULTS

The sample was composed of 27 patients, 63% were male, with a median age of nine days at the first evaluation. Full trisomy of chromosome 13 was the main cytogenetic finding (74%). Only six patients were submitted to obstetric ultrasound and none had prenatal diagnosis of PS. The patients' demographic characteristics, compared to born alive infants in the same Brazilian state showed a higher frequency of: mothers with 35 years old or more (37.5%); multiparous mothers (92.6%); vaginal delivery (77%); preterm birth (34.6%); birth weight <2500g (33.3%), and Apgar scores <7 in the 1st (75%) and in the 5th minute (42.9%). About half of them (53%) died during the first month of life.

CONCLUSIONS

The understanding of the PS patients' gestational, perinatal and family findings has important implications, especially on the decision about the actions to be taken in relation to the management of these patients.

The natural history of pregnancies with a diagnosis of trisomy 18 or trisomy 13; a retrospective case series

BACKGROUND

Trisomy 18 (T18) and trisomy 13 (T13) are the second and third commonest autosomal aneuploidy syndromes respectively. While specific aspects of affected pregnancies have been documented in the literature, few studies document the overall natural history of the trisomies. This study aimed to examine the natural history (including diagnosis, pregnancy outcome, complications and survival) of T18 and T13 pregnancies in a setting where termination of pregnancy for fetal abnormality is not available.

METHODS

Cases were identified using birth registers, labour ward records, annual reports, medical records, ultrasound reports and reports from prenatal genetic testing. All identified T18 and T13 pregnancies in the study region from 2001 to 2012 were included. Individual chart reviews were performed for each case. Data were analysed using SPSS Version 20.

RESULTS

Forty-six T18 and twenty-four T13 pregnancies were identified. Most T18 cases (65%) were diagnosed prenatally, while only one third (33%) of T13 cases were prenatally diagnosed. Only three T18 pregnancies and one T13 pregnancy were electively terminated. A proportion of undiagnosed infants were delivered by emergency caesarean section. 48% (T18) and 46% (T13) infants survived following birth, for a median of 1.5 days (T18) and 7 days (T13). One T13 infant is currently alive over one year of age.

CONCLUSIONS

This large series provides information for professionals and women regarding the natural histories of trisomies 18 and 13. These pregnancies can go undiagnosed antenatally without routine anomaly scanning. While many fetuses die in-utero, postnatal survival is possible.

Better prognosis in newborns with trisomy 13 who received intensive treatments: a retrospective study of 16 patients

Intensive treatment for newborns with trisomy 13 is controversial because of their lethal prognosis. We report the better life prognosis of patients with trisomy 13 who received intensive treatment. At our hospital, we provided an intensive management to such patients including resuscitation and surgical procedures as required. Herein, we present the results of a retrospective study (1989–2010) of 16 trisomy 13 cases who received an intensive treatment. None was diagnosed to have trisomy 13 before birth; 9 were delivered by C-section and oxygen was administered to all patients during postpartum resuscitation. Mechanical ventilation was used in 9 patients after tracheal intubation and tracheotomy was performed in 2 patients when withdrawing of extubation was difficult. Regarding prognosis, 9 patients died, 3 were referred to another hospital, and 4 were discharged from the hospital. Four and 7 patients died within 7 and 30 days after birth, respectively. Nine patients survived for >1 month, 7 for >180 days, and 5 for >3 years. Median survival for 16 patients was 733 days. The patients who received intensive treatments survived longer compared to the previous data. This study provides useful information concerning genetic counseling, especially from an ethical point of view, before providing intensive management to newborns with trisomy 13.

Duplication of the ZIC2 gene is not associated with holoprosencephaly

Cytogenetic testing using genomic microarrays presents a clinical challenge when data regarding the phenotypic consequences of the genomic alteration are not available. We describe a chromosome 13q32.3 duplication discovered by microarray testing in a fetus with a prenatally detected apparently balanced de novo translocation 46,XY,t(2;13)(q37;q32). Microarray analysis on the fetal DNA showed duplications of 384 and 564 kb at the breakpoint regions on chromosomes 2q37.3 and 13q32.3, respectively. There were no disease-associated genes in the duplicated region on chromosome 2q37. The duplicated region on chromosome 13q contains the ZIC2 gene. Haploinsufficiency of ZIC2 is known to cause holoprosencephaly and other brain malformations. Studies in the mouse models have suggested that over expression of ZIC2 may also lead to brain malformations. Fetal MRI of the brain was normal and the family elected to continue the pregnancy. An apparently normal baby was born at term. At 3 months of age a physical exam showed no abnormalities and no developmental delay. This report shows that duplication of ZIC2 is not necessarily associated with brain malformations. We also describe the phenotype from four additional patients with duplications of the region of chromosome 13 containing ZIC2 and three previously described patients with supernumerary marker chromosomes derived from distal chromosome 13. None of the eight patients had holoprosencephaly or brain malformations, indicating that duplication of ZIC2 is not associated with brain anomalies. This information will be useful for counseling in other occurrences of this duplication identified by microarray.

Prenatal diagnosis of a partial trisomy 13q (q14-->qter): phenotype, cytogenetics and molecular characterization by spectral karyotyping and array comparative genomic hybridization

Partial trisomy 13q is an uncommon chromosomal abnormality with variable phenotypic expression. We report prenatal diagnosis of partial trisomy 13q in a fetus with partial agenesis of the cerebellar vermis, partial agenesis of the corpus callosum, hydrops and polyhydramnios. G-banding karyotyping, spectral karyotyping and array comparative genomic hybridization (aCGH) analysis of fetal blood were performed. Cytogenetic analysis of fetal blood displayed 46,XX,add(4)(q28). The parental karyotypes were normal. A girl was delivered at 34 weeks gestation; she died within 2 h. Autopsy confirmed all the prenatal findings and also showed agenesis of the diaphragm. Spectral karyotyping identified the additional material's origin as chromosome 13. aCGH was carried out and showed amplification of distal regions of the long arm of chromosome 13 from region 13q14 to qter. This is the first report of a fetus with molecular characterization of a partial trisomy 13q (q14-->qter), present as a de novo unbalanced translocation at chromosome 4q. This case demonstrates the usefulness of molecular characterization of malformed fetuses for prenatal diagnosis and counseling.

Holoprosencephaly due to numeric chromosome abnormalities

Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE.

Partial trisomy 13q22-qter associated to leukoencephalopathy and late onset generalised epilepsy

The partial trisomy 13q.22 is an uncommon chromosomopathy. We present a case with a partial trisomic component 13q22 and a monosomic component 5p15 from paternal origin. This patient developed early menopause and major neurological disorders as leukoencephalopathy, late onset generalised epilepsy and stroke. She also had fatty acids disturbances and their potential relation to the neurological disorders and early menopause is discussed. The presented case illustrates the phenotype of 13q22-qter in adult age and reaffirms the importance of studying the karyotype of any patient with seizures or leukoencephalopathy particularly when there are associated other clinical features including stroke at a young age, fatty acids disturbances, microcephaly, hypotelorism, short neck, hemangiomata, short fingers or distal swell in thumbs.