Prenatal diagnosis of 18p deletion and 8p trisomy syndrome: literature review and report of a novel case.

18p deletion syndrome constitutes one of the most frequent autosomal terminal deletion syndromes, affecting one in 50,000 live births. The syndrome has un-specific clinical features which vary significantly between patients and may overlap with other genetic conditions. Its prenatal description is extremely rare as the fetal phenotype is often not present during pregnancy. Trisomy 8p Syndrome is characterized by heterogenous phenotype, with the most frequent components to be cardiac malformation, developmental and intellectual delay. Its prenatal diagnosis is very rare due to the unspecific sonographic features of the affected fetuses. We present a very rare case of a fetus with multiple anomalies diagnosed during the second trimester whose genomic analysis revealed a 18p Deletion and 8p trisomy Syndrome. This is the first case where this combination of DNA mutations has been described prenatally and the second case in general. The presentation of this case, as well as the detailed review of all described cases, aim to expand the existing knowledge regarding this rare condition facilitating its diagnosis in the future.

Caregiver perspectives on patient-focused drug development for Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid syndrome (PMS) is a neurodevelopmental disorder caused by SHANK3 haploinsufficiency with clinical manifestations that can be devastating and profoundly affect quality of life. RESULTS: The Externally Led Patient-Focused Drug Development (EL-PFDD) meeting was an opportunity for families affected by PMS to share with the Food and Drug Administration (FDA) how symptoms impact their lives and how treatments could be most meaningful. The Voice of the Patient report serves as a summary of this meeting to influence upcoming drug development and clinical trials. The purpose of this report is to provide a clinical perspective on the results of the EL-PFDD meeting to amplify the voice of these caregivers to the scientific community. CONCLUSIONS: Caregivers prioritize an improved quality of life for their loved ones characterized by improved cognitive function, improved communication, increased independence, and reduced risk of regression. With these caregiver priorities in mind, this report provides the FDA and the scientific community with a clear understanding of which aspects of PMS should influence the development of future therapeutics.

Trisomy 22 Mosaicism from Prenatal to Postnatal Findings: A Case Series and Systematic Review of the Literature.

BACKGROUND: Among aneuploidies compatible with life, trisomy 22 mosaicism is extremely rare, and only about 25 postnatal and 18 prenatal cases have been described in the literature so far. The condition is mainly characterized by facial and body asymmetry, cardiac heart defects, facial dysmorphisms, growth failure, delayed puberty, and variable degrees of neurodevelopmental delay. PROBLEM: The scattered information regarding the condition and the dearth of data on its natural history and developmental outcomes restrict genetic counseling, particularly in prenatal settings. Moreover, a prompt diagnosis is frequently delayed by the negative selection of trisomic cells in blood, with mosaicism percentage varying among tissues, which often entails the need for further testing. Purpose/topic: The aim of our work is to provide assistance in prenatal and postnatal genetic counseling by systematically delineating the current knowledge of the condition. This entails defining the prenatal and postnatal characteristics of the condition and presenting novel data from three cases, both prenatally and postnatally. Additionally, we report the developmental outcomes observed in two new patients.

A rapid PCR-free next-generation sequencing method for comprehensive diagnosis of chromosome disease syndromes in prenatal samples.

The aim of this study is to investigate the application performance of rapid copy number variation sequencing (rCNV-seq) technology for the detection of chromosomal abnormalities during prenatal diagnosis. Samples were collected from 424 pregnant women who were at high-risk for noninvasive prenatal screening in Kunming Maternal and Child Care Hospital from January 2018 to May 2022. rCNV-seq technique was used to detect fetal chromosome abnormalities and compare the results with that of chromosomal karyotype analysis. The Result showed that 330 (77.83%, 330/424) cases indicated chromosomal abnormalities among 424 high-risk pregnant women who underwent rCNV-seq. Moreover, 94 (22.17%, 94/424) cases were discovered to have copy number variations. Among the 330 fetuses with chromosomal abnormalities, common autosomal aneuploidy was observed in 203 cases (47.87%, 203/424) and sex chromosome aneuploidy was observed in 91 cases (21.46%, 91/424). Moreover, the abnormalities in multiple chromosomes were discovered in 33 cases (7.78%, 33/424), and the rare autosomal aneuploidy was observed in 3 cases (0.71%, 3/424). There were 63 fetuses (14.86%, 63/424) with pathogenic CNVs among the 94 fetuses with variable copy numbers. Of the 245 pregnant women who voluntarily selected G-band karyotyping, 1 fetus with copy number variation had normal karyotype results, and the remaining women were consistent with rCNV-seq. Our study revealed that rCNV-seq has higher accuracy in detecting common trisomy and can also detect chromosomal microdeletions or microduplications that cannot be detected by G-banding karyotype analysis. There is no effective treatment for chromosomal diseases, so it is particularly important to prevent chromosomal diseases through genetic counseling and prenatal diagnosis of chromosomal diseases.

Copy number variation sequencing for the products of conception: What is the optimal testing strategy.

BACKGROUND: Copy number variation sequencing (CNV-seq) is crucial in prenatal diagnosis, but its limitations in detecting polyploidy, maternal cell contamination (MCC), and uniparental disomy (UPD) restrict its application in the analysis of products of conception (POCs). This study aimed to investigate an optimal genetic testing strategy for POCs in the era of CNV-seq. METHODS: CNV-seq and quantitative fluorescent polymerase chain reaction (QF-PCR) were performed in all 4,211 spontaneous miscarriage cases. Different testing strategies were compared and the optimal testing strategies were proposed. RESULTS: Of the 4,211 cases, 2561 (60.82%) exhibited clinically significant chromosomal abnormalities. CNV-seq alone, without QF-PCR, might misdiagnose 311 (7.39%) cases, including 278 polyploidy, 13 UPD, and 20 MCC. In 20 MCC cases identified by QF-PCR, CNV-seq successfully pinpointed the cause of miscarriage in 13 cases. Furthermore, in cases where QF-PCR suggested polyploidy, CNV-seq improved the diagnostic accuracy in 54 (1.28%) hypo/hypertriploidy cases. After comparing four different strategies, the sequential approach (initiating with CNV-seq followed by QF-PCR if necessary) emerged as advantageous, reducing approximately 70% of the cost associated with QF-PCR while maintaining result accuracy. CONCLUSIONS: We propose an initial CNV-seq followed by QF-PCR if needed-an efficient and cost-effective strategy for the genetic analysis of POCs.

[Analysis of genetic etiology in a patient with 1p36 deletion syndrome in conjunct with Snijders Blok-Campeau syndrome].

OBJECTIVE: To explore the genetic basis for a patient with unexplained developmental delay and special facial features. METHODS: A male patient admitted to the Maternal and Child Health Care Hospital of Gansu Province on May 27, 2021 due to infertility was selected as the study subject. Clinical data of the patient was collected, and genomic DNA was extracted from peripheral blood samples from the patient and his parents. Whole exome sequencing (WES) was carried out, and candidate variant was verified by Sanger sequencing. RESULTS: The patient was found to harbor a 2.54 Mb deletion in 1p36.33p36.32 and a heterozygous c.1123G>C (p.E375Q) variant of the CHD3 gene, neither of which was detected in his parents. CONCLUSION: The patient was diagnosed with Snijders Blok-Campeau syndrome in conjunct with 1p36 deletion syndrome, which has enabled genetic counseling for his family.

Constitutional chromosomal anomalies in children, fetal alcohol syndrome, and maternal toxicant exposures: A longitudinal cohort study.

DNA alterations in gametes, which may occur either spontaneously or as a result of exposure to genotoxicants, can lead to constitutional chromosomal anomalies in the offspring. Alcohol is an established genotoxicant. The goal of this hypothesis-testing longitudinal cohort study was to evaluate the effect of significant/sustained maternal alcohol exposure on clinically diagnosed constitutional chromosomal anomalies among children diagnosed with fetal alcohol syndrome (FAS). De-identified eligibility and claim healthcare records, prospectively generated from the 1990-2012 Florida Medicaid system within the Independent Healthcare Research Database (IHRD), were analyzed. Children examined were continuously eligible with ≥ 8 outpatient office visits during the 96-month period following birth. Among these children, 377 were diagnosed with FAS and 137,135 were not. The incidence rate of chromosomal anomalies involving segregation (trisomy 13, 18, or 21, n = 625), microdeletions (microdeletion syndromes, n = 39), and point mutations (sickle-cell anemia/cystic fibrosis, n = 2570) were examined using frequency risk ratio (RR) and logistic regression (adjusted odds ratio (aOR) for sex, race, residence, socioeconomic/environmental exposure status, and birth date) models. The incidence rates of chromosomal anomalies involving segregation (RR=5.92, aOR=5.85) and microdeletions (RR=41.6, aOR=34.1) were significantly increased in the FAS cohort as compared to the non-diagnosed cohort, but there was no difference in the incidence rate of point mutations (RR=1.14, aOR=1.29). Maternal toxicant exposure should be considered in the etiology of constitutional chromosomal anomaly in offspring.

Chromosome balanced translocation in newborn fetus founded during prenatal diagnosis: Three cases reports.

RATIONALE: Because of the normal phenotype, carriers of specific chromosomal translocations are often diagnosed only after their development of associated malignancies, recurrent miscarriages, and reproductive difficulties. In this paper, we report primary balanced fetal chromosomal translocations by performing the necessary invasive prenatal diagnosis in couples with previous malformations coupled with prenatal testing suggesting a high risk for trisomy 21. PATIENT CONCERNS: Case 1 and Case 2 couples had malformed children, and Case 3 couples had a high risk of trisomy 21 on noninvasive preconception serological testing. DIAGNOSIS AND INTERVENTION: A balanced chromosomal translocation diagnosis was confirmed by karyotyping of fetal cells obtained by amniocentesis. OUTCOMES: All 3 couples decided to continue their pregnancies after learning about the consequences of the chromosomal abnormalities. Approximately a year after the children were born, the staff of the Prenatal Diagnostic Center followed up with a phone call and found that the children physical development and intelligence were normal. LESSON: This case report reports healthy chromosomal balanced translocation newborns born to couples with poor maternal history and couples with abnormalities suggested by preconception testing, and followed up with the newborns to provide some experience in prenatal diagnosis and genetic counseling for chromosomal balanced translocations.

Structural brain abnormalities in Pallister-Killian syndrome: a neuroimaging study of 31 children.

BACKGROUND: Pallister-Killian syndrome (PKS) is a rare genetic disorder caused by mosaic tetrasomy of 12p with wide neurological involvement. Intellectual disability, developmental delay, behavioral problems, epilepsy, sleep disturbances, and brain malformations have been described in most individuals, with a broad phenotypic spectrum. This observational study, conducted through brain MRI scan analysis on a cohort of patients with genetically confirmed PKS, aims to systematically investigate the neuroradiological features of this syndrome and identify the possible existence of a typical pattern. Moreover, a literature review differentiating the different types of neuroimaging data was conducted for comparison with our population. RESULTS: Thirty-one individuals were enrolled (17 females/14 males; age range 0.1-17.5 years old at first MRI). An experienced pediatric neuroradiologist reviewed brain MRIs, blindly to clinical data. Brain abnormalities were observed in all but one individual (compared to the 34% frequency found in the literature review). Corpus callosum abnormalities were found in 20/30 (67%) patients: 6 had callosal hypoplasia; 8 had global hypoplasia with hypoplastic splenium; 4 had only hypoplastic splenium; and 2 had a thin corpus callosum. Cerebral hypoplasia/atrophy was found in 23/31 (74%) and ventriculomegaly in 20/31 (65%). Other frequent features were the enlargement of the cisterna magna in 15/30 (50%) and polymicrogyria in 14/29 (48%). Conversely, the frequency of the latter was found to be 4% from the literature review. Notably, in our population, polymicrogyria was in the perisylvian area in all 14 cases, and it was bilateral in 10/14. CONCLUSIONS: Brain abnormalities are very common in PKS and occur much more frequently than previously reported. Bilateral perisylvian polymicrogyria was a main aspect of our population. Our findings provide an additional tool for early diagnosis.Further studies to investigate the possible correlations with both genotype and phenotype may help to define the etiopathogenesis of the neurologic phenotype of this syndrome.

Epidemiological Assessment of a Pediatric Palliative Care Clinic at a Brazilian Quaternary Hospital: 20 Years of Experience.

Background: The pediatric palliative care (PPC) sets up an interdisciplinary approach of chronic complex diseases throughout birth to adolescence. It encompasses countless contrasts in development and diagnosis scopes, which make this area a challenge to nonpediatric practitioners. Objective: We sought to assess the most prevalent diseases in follow-up of the PPC team. Methods: We analyzed the medical records of PPC clinic during the years 2001 and 2021 and the diagnosis of outpatients. We established a parallel with the world scientific literature concerning the epidemiology of PPC. Results: The most prevalent diseases were epidermolysis bullosa (36.9%), followed by neurological Inherited Errors of Metabolism (IEM) diseases (19.0%), IEM diseases (14.3%), dysmorphological and chromosomal disorders (8.5%), skeletal disorders mainly osteogenesis imperfecta (6.9%), and liver transplantation conditions (5.5%) (p < 0.001). The less frequent conditions were external causes, such as neonatal insults or traffic accidents (2.8%), cancer (1.7%), congenital cardiopathies (1.4%), congenital infectious diseases (1.1%), gastrointestinal and hepatic conditions (0.8%), and rheumatological conditions (0.3%). The patients were older at diagnosis (6.9 years) and at PPC referral (13.2 years) than patients with epidermolysis bullosa and skeletal disorders and dysmorphological and chromosomal disorders were younger on referral. Conclusion: There are a lot of complex chronic conditions which could benefit from palliative care in pediatric setting. However, epidemiological and symptomatological assessment of the health service is necessary to provide an appropriate care to the country's reality.

Evidence for common mechanisms of pathology between SHANK3 and other genes of Phelan-McDermid syndrome.

Chromosome 22q13.3 deletion (Phelan-McDermid) syndrome (PMS, OMIM 606232) is a rare genetic condition that impacts neurodevelopment. PMS most commonly results from heterozygous contiguous gene deletions that include the SHANK3 gene or likely pathogenic variants of SHANK3 (PMS-SHANK3 related). Rarely, chromosomal rearrangements that spare SHANK3 share the same general phenotype (PMS-SHANK3 unrelated). Very recent human and model system studies of genes that likely contribute to the PMS phenotype point to overlap in gene functions associated with neurodevelopment, synaptic formation, stress/inflammation and regulation of gene expression. In this review of recent findings, we describe the functional overlaps between SHANK3 and six partner genes of 22q13.3 (PLXNB2, BRD1, CELSR1, PHF21B, SULT4A1, and TCF20), which suggest a model that explains the commonality between PMS-SHANK3 related and PMS-SHANK3 unrelated classes of PMS. These genes are likely not the only contributors to neurodevelopmental impairments in the region, but they are the best documented to date. The review provides evidence for the overlapping and likely synergistic contributions of these genes to the PMS phenotype.

The Evaluation of Invasive Prenatal Diagnostic Tests in North Cyprus: A Retrospective Study.

BACKGROUND: Congenital diseases are still an important medical, social, and economic problem all over the world. In North Cyprus, in addition to other reasons, early prenatal diagnostic measures are undertaken to prevent births with thalassemia major, a locally widespread genetic disease. AIM: This study aims to evaluate the results of prenatal invasive diagnostic tests performed in a private obstetrics clinic in Northern Cyprus and show the diagnosis process of thalassemia and chromosomal anomalies. MATERIALS AND METHODS: This study is a retrospective, descriptive study. Chorionic villus sampling (CVS) results and the amniocentesis tests performed between 1990 and 2022 are evaluated. Thalassemia and chromosome analysis of samples obtained by CVS and amniocentesis tests were performed. To diagnose alpha or beta thalassemia and sickle cell, 239 CVS was performed. And to diagnose chromosomal anomalies, 396 CVS and amniocentesis were performed. RESULTS: The mean age of the 480 pregnant women included in the study was 31.12 years (18-46) and 30% of them were older than 34 years. The most common indications for invasive prenatal diagnostic test (IPDT) were; mother/father thalassemia minor/major, advanced maternal age, high risk of ultrasonography erase findings, and the noninvasive screening test. The result of IPDT detected 7.3% chromosomal anomaly and 69.5% thalassemia and sickle cell anemia. Of the 239 CVS performed to diagnose alpha or beta thalasemia and sickle cell, 23.4% beta major, 42.3% beta minor, and 2.1% alpha minor were diagnosed. Of the 396 CVS and amniocentesis performed to diagnose chromosomal anormalies; 2.8% of Down syndrome and 4.54% of other chromosomal anomalies were diagnosed. CONCLUSION: IPDT is important in correctly diagnosing fetal anomalies at the prenatal stage to help families decide at the right time.

[Prenatal diagnosis and phenotypic analysis of two fetuses harboring heterozygous deletions of SHOX gene].

OBJECTIVE: To explore the clinical manifestations of two fetuses harboring heterozygous deletions of the SHOX gene. METHODS: Two pregnant women who had presented at the Prenatal Diagnosis Center of Nanjing Drum Tower Hospital respectively on June 24, 2022 and July 27, 2022 were selected as the study subjects. In case 1, prenatal ultrasonography had shown short femur and intrauterine growth retardation of the fetus. Case 2 had a history of spontaneous abortions due to structural chromosomal aberrations. Fetus 1 had undergone a test for the FGFR3 gene, and both fetuses were subjected to single nucleotide polymorphism-based microarray (SNP array) analysis. RESULTS: After excluding the influence of FGFR3 gene variant, fetus 1 was found to harbor a heterozygous 883 kb deletion at Xpter or Ypter, whilst fetus 2 was found to harbor a 5.75 Mb deletion in the Xpter region. Both deletions have encompassed the SHOX gene. The origin of the deletion in fetus 1 was unknown, whilst that in fetus 2 was inherited from its mother. Fetus 1 has been delivered at term with a normal phenotype, and fetus 2 was not born yet. CONCLUSION: The intrauterine and postnatal phenotypes of fetuses may be predicted by combining the ultrasound finding, parental phenotype and results of CMA, and the results can facilitate genetic counseling and decision making over the pregnancy.

Cases of trisomy 21 and trisomy 18 among historic and prehistoric individuals discovered from ancient DNA.

Aneuploidies, and in particular, trisomies represent the most common genetic aberrations observed in human genetics today. To explore the presence of trisomies in historic and prehistoric populations we screen nearly 10,000 ancient human individuals for the presence of three copies of any of the target autosomes. We find clear genetic evidence for six cases of trisomy 21 (Down syndrome) and one case of trisomy 18 (Edwards syndrome), and all cases are present in infant or perinatal burials. We perform comparative osteological examinations of the skeletal remains and find overlapping skeletal markers, many of which are consistent with these syndromes. Interestingly, three cases of trisomy 21, and the case of trisomy 18 were detected in two contemporaneous sites in early Iron Age Spain (800-400 BCE), potentially suggesting a higher frequency of burials of trisomy carriers in those societies. Notably, the care with which the burials were conducted, and the items found with these individuals indicate that ancient societies likely acknowledged these individuals with trisomy 18 and 21 as members of their communities, from the perspective of burial practice.

Antenatal description of large 4q13.2q21.23 deletion and outcomes.

BACKGROUND: 4q21 microdeletion syndrome is an emergent non-recurrent genomic disorder characterized by facial dysmorphy, progressive growth retardation, severe intellectual deficit, and absent or severely delayed speech. Deletions occur in clusters along 4q interstitial or terminal regions. 4q chromosomal aberrations are variable in type, size, and breakpoint. Genotype-phenotype correlation is a challenging task. The recurrent antenatal feature associated a posteriori with this syndrome is intrauterine growth retardation. There are very few precise antenatal descriptions of this syndrome. METHODS: We report here the first antenatal history of one of the largest deletion of this region. RESULTS: Our case harbored a 16.9 Mb deletion encompassing 135 protein coding genes including 20 OMIM morbid genes involved in neurological and cognitive abilities. Those breakpoints overlap two clusters of described microdeletion syndromes of cytogenetic band 4q13 and 4q21. CONCLUSION: From the end of the second trimester, set of call signs associated with this syndrome can be completed by: excess of amniotic fluid, mild growth retardation, short long bones, bony anomalies of the extremities, and bulging cheeks. So, emphasis should be placed on the examination of the extremities, and the face during the routine targeted prenatal ultrasound.

The Pivotal Role of Oxytocin's Mechanism of Thermoregulation in Prader-Willi Syndrome, Schaaf-Yang Syndrome, and Autism Spectrum Disorder.

Oxytocin (Oxt) regulates thermogenesis, and altered thermoregulation results in Prader-Willi syndrome (PWS), Schaaf-Yang syndrome (SYS), and Autism spectrum disorder (ASD). PWS is a genetic disorder caused by the deletion of the paternal allele of 15q11-q13, the maternal uniparental disomy of chromosome 15, or defects in the imprinting center of chromosome 15. PWS is characterized by hyperphagia, obesity, low skeletal muscle tone, and autism spectrum disorder (ASD). Oxt also increases muscle tonicity and decreases proteolysis while PWS infants are hypotonic and require assisted feeding in early infancy. This evidence inspired us to merge the results of almost 20 years of studies and formulate a new hypothesis according to which the disruption of Oxt's mechanism of thermoregulation manifests in PWS, SYS, and ASD through thermosensory abnormalities and skeletal muscle tone. This review will integrate the current literature with new updates on PWS, SYS, and ASD and the recent discoveries on Oxt's regulation of thermogenesis to advance the knowledge on these diseases.

Pregnant women's informational needs prior to decisions about prenatal diagnosis for chromosomal anomalies-A Q methodological study.

OBJECTIVE: To study pregnant women's subjective viewpoints on what is important when receiving information prior to decision-making regarding prenatal testing for chromosomal anomalies. METHOD: Data were collected using Q methodology. During January 2020-October 2021, 45 pregnant women in Sweden completed a 50-item Q sort. Statements regarding what is important when receiving information about prenatal screening and diagnosis were prioritized through ranking in a fixed sorting grid on an 11-point scale, from "most important" to "least important." Socio-demographics and coping styles were surveyed through questionnaires. RESULTS: Three groups represented different viewpoints on what pregnant women consider important when receiving information about prenatal screening and diagnosis. Factor 1: Stepwise information and decision-making: viewing information and decision-making as a step-by-step process. Factor 2: Decision-making as a continuous process based on couple autonomy: Striving for an informed decision as a couple about tests, test results and conditions screened. Factor 3: As much information as early as possible-the importance of personal autonomy in decision-making: Prioritizing autonomous decision-making based on non-directive information early in the pregnancy. CONCLUSION: This study highlights the complexities involved when providing information. As shown by the differing viewpoints in this study, pregnant women's informational needs differ, making individual and personalized information preferable.