Intellectual, adaptive and behavioural characteristics in four patients with 18p deletion syndrome.

BACKGROUND: The association of behavioural phenotype assessment with cytogenomic characterisation may provide a better comprehension of genotype-phenotype correlations in syndromes caused by chromosomal abnormalities, such as 18p deletion syndrome. METHOD: We report on four Brazilian patients with 18p deletion syndrome characterised by cytogenomic techniques and detailed neuropsychological evaluation. Intellectual, adaptive and behavioural characteristics were assessed through the Wechsler's Scales, the Vineland-II Scale and the Child Behaviour Checklist, respectively. Socio-economic measures including main caretaker educational level and family income as defined by Brazilian criteria for social class classification were also collected to evaluate a possible contribution of environmental factors in neurocognitive variability. RESULTS: Two out of four patients showed intellectual disability (IQ < 70). Wechsler's scale results suggest that in our sample, interpretation of social situations based on observation of non-verbal behaviour constitute a cognitive strength while judgement of social rules and language skills associated with word knowledge and verbal fluency may be a cognitive weakness. Concerning adaptive behaviour, motor and socialisation domains showed to better develop than communication and daily living skills on the Vineland-II Scale. Only one patient presented internalising behavioural problems based on the Child Behaviour Checklist. Our results also suggested that socio-economic status may contribute to overall patient development. CONCLUSION: Our results suggest that some 18p deletion syndrome patients may present average intellectual performance and that the segment deletion size and some families' socio-economic conditions may influence cognitive development.

Desirable quality-control materials for the establishment of qualified external quality assessment on prenatal diagnosis of chromosomal aneuploidies.

OBJECTIVE: To prepare desirable quality-control materials for the establishement of qualified external quality assessment on fluorescence in situ hybridization (FISH)-detected prenatal diagnosis of chromosomal aneuploidies. METHODS: Four types of amniotic fluid cell suspensions (13-trisomy, 18-trisomy, 21-trisomy and 47,XXY) were mixed together by ratio to produce mosaicism with the percentages of each aneuploidy as 10%, 20%, 30% and 40%, respectively. After being stored in liquid nitrogen of -196 °C for six months, randomly selected samples were incubated in 37 °C water, followed by cultivation, hypo-osmosis and fixation. Finally, FISH detetion was applied on them before and after external laboratory mailing, in step with detection on conventional case samples. RESULTS: Before mailing, the positive rates of each aneuploidy described above were 12.8%, 23.6%, 33.8%, 44.0%, while 12.6%, 23.8%, 34.0%, 43.5% after mailing. t-test, criteria for stability assessment of quality-control materials in CANS-GL03:2006, showed no significant effect of external mailing on mosaicism since corresponding t values are lower than threshold with significance level α as 0.05 and degree of freedom as 10. CONCLUSION: As FISH detection showed, the mosaic cell strains prepared in current study exhibited excellent stabilities after cryopreservation in -196 °C, subculture, hypo-osmosis, fixation and external laboratory mailing, demonstrating them as reliable and promising quality-control materials for the establishment of a qualified external quality assessment on prenatal diagnosis of chromosomal aneuploidies.

A cost-effectiveness analysis comparing two different strategies in advanced maternal age: Combined first-trimester screening and maternal blood cell-free DNA testing.

OBJECTIVE: To estimate cost efficacy of first-trimester screening strategies based on nuchal translucency (NT) and maternal blood cell-free DNA (cfDNA) testing in women with advanced maternal age (AMA). MATERIALS AND METHODS: This was a retrospective population-based analysis of all pregnant women with AMA booked for combined first-trimester screening (cFTS) in China over a 3-year period. The assumed screening strategies were the following: cFTS (Strategy 1), cfDNA testing as a first-tier investigation replacing biomarkers after NT measurement (Strategy 2), and cfDNA testing combined with dating ultrasound for all women (Strategy 3). The direct costs were compared between strategies. RESULTS: Strategy 1 was completed in 6443 women with AMA. The respective detection rates were 94.5% and 90.9% for trisomies 21 and 18, with a total screen-positive rate of 13.5%. Such a policy resulted in 871 invasive tests and a total cost of $747,870 or a cost of $116 per person tested. Strategy 2 would result in a total cost of $1,812,570, or a cost of $281 per person tested, with increased detection rates for trisomies 21 and 18, and a decreased number of invasive tests compared with strategy 1. The total cost of Strategy 3 would be $1,675,430, or a cost of $260 per person tested with the least number of invasive tests. CONCLUSION: The cfDNA modalities have the advantages of higher detection rate for common trisomies and lower screening-positive rate. However, the cost of cfDNA testing needs to decrease significantly if it is to replace the current cFTS practice in a population of AMA on a purely cost effectiveness basis.

Genotype-Phenotype Analysis, Neuropsychological Assessment, and Growth Hormone Response in a Patient with 18p Deletion Syndrome.

18p deletion syndrome is a rare chromosomal disease caused by deletion of the short arm of chromosome 18. By using cytogenetic and SNP array analysis, we identified a girl with 18p deletion syndrome exhibiting craniofacial anomalies, intellectual disability, and short stature. G-banding analysis of metaphase cells revealed an abnormal karyotype 46,XX,del(18)(p10). Further, SNP array detected a 15.3-Mb deletion at 18p11.21p11.32 (chr18:12842-15375878) including 61 OMIM genes. Genotype-phenotype correlation analysis showed that clinical manifestations of the patient were correlated with LAMA1, TWSG1, and GNAL deletions. Her neuropsychological assessment test demonstrated delay in most cognitive functions including impaired mathematics, linguistic skills, visual motor perception, respond speed, and executive function. Meanwhile, her integrated visual and auditory continuous performance test (IVA-CPT) indicated a severe comprehensive attention deficit. At age 7 and 1/12 years, her height was 110.8 cm (-2.5 SD height for age). Growth hormone (GH) treatment was initiated. After 27 months treatment, her height was increased to 129.6 cm (-1.0 SD height for age) at 9 and 4/12 years, indicating an effective response to GH treatment.

Joint Assessment of Donor and Recipient hTERT Gene Polymorphism Provides Additional Information for Early Kidney Transplantation Outcomes.

BACKGROUND There are several genes and genetic loci affecting telomere length, including hTERT gene and BICD1 gene as well as polymorphisms within chromosome 18. It has been demonstrated that the age of the donor is a negative factor associated with long-term kidney allograft function, and that post-transplant complications accelerate transplanted organ aging, thus contributing to estimated glomerular filtration rate (eGFR) decreases. The aim of this study was a joint assessment of donors' and recipients' hTERT and BICD1 genes as well as chromosome 18 polymorphisms with regard to early kidney transplantation outcomes. MATERIAL AND METHODS The study enrolled 74 pairs of Polish Caucasian kidney allograft cadaveric donors (60% male, mean age 45.99±14.62) and recipients (50.0% male, mean age 48.89±13.50). The transplantation procedure (Tx) was performed between 2001 and 2012. All samples were genotyped in duplicate using Real-Time PCR. RESULTS This study showed that rs2735940 hTERT CX-TT donor-recipient genotype pair was associated with almost five times higher odds (OR=4.82; 95% CI: 1.32-18; p=0.016) of delayed graft function (DGF), and that rs2735940 hTERT, rs2630578 BICD1, and rs7235755 chromosome 18 polymorphisms combined pairs were not associated with acute rejection (AR). CONCLUSIONS In conclusion, both the donor's and the recipient's rs2735940 hTERT gene polymorphism was associated with early graft function after transplantation. The odds of DGF were almost five times higher for a combination of CX (CT or CC) donor genotype and TT recipient genotype. Joint assessment of donor-recipient genotype pairs provides more information for prediction of early kidney transplantation outcomes.

First trimester contingent screening for trisomies 21,18,13: is this model cost efficient and feasible in public health system?

PURPOSE: To evaluate the effectiveness of three different first trimester screening models for trisomies 21, 18 and 13, in terms of detection rate, invasive test rate and final costs. MATERIAL AND METHODS: We analyzed the distribution of risk for trisomies 21, 18 and 13 in a population of 20,831 singleton pregnancies based on maternal age, fetal heart rate, nuchal translucency, free beta human chorionic gonadotropin and pregnancy-associated plasma protein A (Combined test). On the basis of our data, we estimated the performance and cost of screening for trisomies using three different models at specific cutoffs: Combined test; Cell free DNA test and Contingent screening test. RESULTS: Using Combined test, DR for major trisomies was estimated to be 94.92%, invasive test rate was 6.3%. cfDNA would result in a DR of 97.92%, with an invasive test rate of 3.64%. Contingent screening approach would result in an overall DR of 97.82, with a rate for invasive procedure of 1.36% and a final cost lower than other screening policies (2,338,433 euro vs 5,796,060 of cfDNA and 2,385,473 of Combined test). CONCLUSIONS: Contingent screening test could be a cost-efficient and feasible first trimester screening test for aneuploidies in public health system.

Segmental Duplication QF-PCR: A Simple and Alternative Method of Rapid Aneuploidy Testing for Developing Country Like India.

BACKGROUND: Aneuploidy screening is becoming an integral part of routine prenatal screening in developing countries like India, and the need for more cheaper and rapid aneuploidy testing methods are required to relive the anxiety and financial burden among the high-risk couples. Segmental duplication quantitative fluorescent polymerase chain reaction (SD-QF-PCR) emerged as an alternative aneuploidy diagnostic method. METHODS: This study was conducted to optimize and access the utility of SD-QF-PCR in routine prenatal diagnosis to complement existing short tandem repeats (STR) based QF-PCR. About 50 control samples, 50 Down's syndrome samples, and one each trisomy 18 and Klinefelter samples were studied to optimize the assay. Later, 100 amniotic fluid samples were also studied. RESULTS AND CONCLUSION: The assay was able to successfully identify normal and aneuploidy samples with 100% sensitivity and specificity. The results of amniotic fluid analysis by SD-QF-PCR were in agreement with results of STR-QF-PCR. Observed results qualify SD-QF-PCR as a preliminary aneuploidy diagnosis method.

Cardiac surgery for children with trisomies 13 and 18: Where are we now?

The objective is to examine whether cardiac surgery should be considered for children with trisomy 13 or 18 (T13 or 18).T13 or 18 were previously referred to as "lethal" conditions due to high mortality rates and severe disability among survivors. In the last decade, investigations have revealed these conditions are heterogeneous, with increasing numbers of studies describing interventions for these children. A number of factors makes the interpretation of reported outcomes after cardiac surgery challenging: (1) dissimilarities in practice lead to a wide variation in reported outcomes after cardiac surgery; (2) cardiac surgery is generally offered to older, healthier children; (3) cardiac surgeries of widely varying risks are often lumped together in individual studies, and (4) cases where cardiac surgery has been withheld are generally not included in publications. It is unclear whether withholding cardiac surgery for some children with a ventricular septal defect will lead to death, or the development of pulmonary hypertension, or if death will occur from other causes. In this article, we describe two children with different clinical situations and examine whether cardiac surgery would benefit them and how to communicate with their families. Cardiac surgery may be beneficial to some children with trisomy 13 or 18, but may harm others. Every child should be approached in an individual fashion and the goals of each family should be addressed. Children who are more likely to benefit from surgery may be older, healthier children without respiratory support. Rigorous and transparent research is needed to identify factors that affect survival in trisomy 13 or 18.

External Quality Assessment for Detection of Fetal Trisomy 21, 18, and 13 by Massively Parallel Sequencing in Clinical Laboratories.

An external quality assessment for detection of trisomy 21, 18, and 13 by massively parallel sequencing was implemented by the National Center for Clinical Laboratories of People's Republic of China in 2014. Simulated samples were prepared by mixing fragmented abnormal DNA with plasma from non-pregnant women. The external quality assessment panel, comprising 5 samples from pregnant healthy women, 2 samples with sex chromosome aneuploidies, and 13 samples with different concentrations of fetal fractions positive for trisomy 21, 18, and 13, was then distributed to participating laboratories. In total, 55.6% (47 of 84) of respondents correctly identified each of the samples in the panel. Seventeen false-negative and 87 gray zone results were reported, most [102 of 104 (98.1%)] of which were derived from for trisomy samples with effective fetal fractions <4%. No laboratories generated false-positive results. In addition, we observed varied diagnostic capabilities of different assays, with the assay on the basis of NextSeq CN500 performing better than others, whereas Z values generated by BGISEQ-100 fluctuated greatly. There were no significant correlations between the numbers of unique sequence reads and Z values from any trisomy sample generated by BGISEQ-100. Overall, most clinical laboratories detected samples containing effective fetal fractions >4%. Our study shows need for further laboratory training in the management of samples with low fetal fractions. For some assays, precision of Z values needs to be improved.

Prenatal diagnosis of fetuses with increased nuchal translucency using an approach based on quantitative fluorescent polymerase chain reaction and genomic microarray.

OBJECTIVE: To assess the clinical value of prenatal diagnosis of fetuses with increased nuchal translucency (NT) using an approach based on quantitative fluorescent polymerase chain reaction (QF-PCR) and chromosomal microarray (CMA). STUDY DESIGN: From January 2013 to October 2014, we included 175 pregnancies with fetal NT ≥ 3.5mm at 11-13 weeks' gestation who received chorionic villus sampling. QF-PCR was first used to rapidly detect common aneuploidies. The cases with a normal QF-PCR result were analyzed by CMA. RESULTS: Of the 175 cases, common aneuploidies were detected by QF-PCR in 53 (30.2%) cases (30 cases of trisomy 21, 12 cases of monosomy X, 7 cases of trisomy 18, 3 cases of trisomy 13 and 1 case of 47, XXY). Among the 122 cases with a normal QF-PCR result, microarray detected additional pathogenic copy number variants (CNVs) in 5.7% (7/122) of cases. Four cases would have expected to be detectable by conventional karyotyping because of large deletions/duplications (>10 Mb), leaving three cases (2.5%; 3/118) with pathogenic CNVs only detectable by CMA. CONCLUSION: It is rational to use a diagnostic strategy in which CMA is preceded by the less expensive, rapid, QF-PCR to detect common aneuploidies. CMA allows detection of a number of pathogenic chromosomal aberrations in fetuses with a high NT.

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.

Antenatal screening for Down's syndrome, trisomy 18, and trisomy 13: Reporting a single screening result for all three.

OBJECTIVE: To compare the performance of antenatal screening for Down's syndrome (DS), trisomy 18 (T18), and trisomy 13 (T13) using a single risk of being affected by one of the three disorders, with the performance using separate risks for each disorder. METHODS: Screening performance was estimated using Monte Carlo simulation based on published parameters for the Integrated, Combined, and Quadruple tests. Detection rates (DRs) were calculated using a single risk and separate risks for each disorder at given false-positive rates (FPRs). RESULTS: With separate risks, using a 3% DS test FPR and 0.2% FPRs for the T18 and T13 tests, the overall FPRs for the Integrated and Combined tests are both 3.3%. For the same overall FPR (3.3%), the use of a single risk with the Integrated test increases the T13 DR from 76% to 82%, with unchanged DS and T18 DRs (94% and 92% respectively). With the Combined test, it increases the T13 and T18 DRs (from 89% to 91% and 77% to 81% respectively), with unchanged DS DR (85%). With separate risks, using a 5% DS test FPR and 0.2% FPRs for the T18 and T13 tests, the overall FPR for the Quadruple test is 5.4%. For the same overall FPR (5.4%), the use of a single risk increases the T18 DR from 61% to 67% with unchanged DS and T13 DRs (87% and 33% respectively). CONCLUSIONS: Reporting a single risk estimate for the three disorders is less confusing than reporting separate risks and can yield the same or better screening performance.

[MODELS OF CLINICAL IMPLEMENTATION OF CELL FREE FETAL DNA IN THE MATERNAL SERUM SCREENING TEST-ANALYSIS].

UNLABELLED: Prenatal screening by definition is a way of identifying pregnancies, with a high enough risk to specific fetal damage as to justify the subsequent invasive diagnosis among the seemingly normal pregnancies. [1] The aim of the prenatal screening test is to reach the high diagnostic frequency (DR > 95%), with low false-positive rate (FPR < 1%). Several non-invasive prenatal tests (NIPT) are widely adopted and use in clinical practice: 1st Trimester Combined screening (First trimester Combined Screening) and 2nd trimester biochemical screening (Second trimester biochemical screening) and in the last few years through screening Fetal DNA in Maternal serum (cfDNA screening). Since the introduction of the sfDNA test were examined and discussed the results of several ways of application: (1) as a primary screening method without preceding the result of 1st trimester combined screening for chromosomal abnormalities, (2) as a contingent test after 1st trimester combined screening in high risk pregnancies (> 1:100) (3) as a contingent test after 1st trimester combined screening, when the calculated risk is between ( 1:10 to 1:2500). The purpose of the study: to compare the results of different ways of application screening through cfDNA: detection rate (DR) for Tri21, Tri18 and Tri13, procentage of invasive diagnostics and cost-effectiveness ratio of cfDNA test in comparison with the 1st trimester combined screening. To establish the most suitable algorithm for application of cfDNA test. METHODS AND MATERIALS: Analyzed were the results of several randomized multi-center clinical studies whose data are processed through a meta-analysis. RESULTS: cfDNA-test has a higher DR for Tri21 for lower FPR, compared to the combined screening in 1st trimester (cfDNA-DR 99%, 1st trimester screening-DR 96% and 0.4%FPR, respectively FPR 5%), but although it is with better results and reduces the incidence of invasive tests, does not justify the significant difference in price-performance ratio. On the other hand cfDNA-test is with a lower detection rate for Tri 18 or 13 (93-95%), which makes it worse for a primary screening test instead of combined screening in the 1st trimester. CONCLUSIONS: The performance of cfDNA-test in terms of the three most common Trisomies: 21,18 and 13 is highest when used after (contingent to) 1st trimester screening and only for patients with an intermediate risk from 1-st trimester screening (risk > 1:10 and 1:2500, around 27% of all pregnancies), as it increases the diagnostic rate of combined screening for Down syndrome (from 90% to 98%), and significantly reduces the percentage of invasive diagnostics (from 3% to 0.7-1%) and that way we are able to achieve optimal result in price-performance result.

Ring 18 molecular assessment and clinical consequences.

Ring chromosome 18 is a rare condition which has predominantly been described by case reports and small case series. We assessed a cohort of 30 individuals with ring 18 using both microarray comparative genomic hybridization (aCGH) and fluorescence in situ hybridization (FISH). We determined that each participant had a unique combination of hemizygosity for the p and q arms. Four ring chromosomes had no detectable deletion of one of the chromosome arms using aCGH. However, two of these ring chromosomes had telomeric sequences detected using FISH. These data confirm the importance of molecular and cytogenetic analysis to determine both chromosome content and morphology. We failed to find dramatic changes in mosaicism percentage between cytogenetic measurements made at the time of diagnosis and those made years later at the time of this study, demonstrating that dynamic ring mosaicism is unlikely to be a major cause of phenotypic variability in the ring 18 population. Lastly, we present data on the clinical features present in our cohort, though the extreme genotypic variability makes it impossible to draw direct genotype-phenotype correlations. Future work will focus on determining the role of specific hemizygous genes in order to create individualized projections of the effect of each person's specific ring 18 compliment.

Socioeconomic disparities in diagnostic testing after positive aneuploidy screening.

OBJECTIVE: The objective of this study was to investigate the association between type of health insurance (Medicaid vs. private) and uptake of diagnostic testing for fetal aneuploidy after a positive screening test result. METHODS: We performed a retrospective cohort study of pregnant women who underwent aneuploidy screening in the first and/or second trimesters of pregnancy and received positive results. The characteristics of and outcomes for women with Medicaid were compared with those of women with private insurance in both univariable and multivariable analyses. RESULTS: In this study, 75 women with Medicaid and 75 with private insurance were analyzed. Those with Medicaid were younger (33.8 vs. 36.9 years, p < 0.01), and more likely to be of non-white race/ethnicity (88 vs. 27%, p < 0.01), unmarried (65 vs. 19%, p < 0.01), non-English speaking (12 vs. 0%, p < 0.01), and multiparous (76 vs. 59%, p = 0.02). They also were less likely to undergo diagnostic testing after a positive aneuploidy screen (35 vs. 57%, p < 0.01). In multivariable analysis, those with Medicaid remained significantly less likely to undergo diagnostic testing (odds ratio, 0.26; 95% confidence interval, 0.09-0.80). CONCLUSION: Women with Medicaid are less likely than women with private insurance to undergo diagnostic testing after positive screening for aneuploidy. These results emphasize the potential importance of improved counseling for low-income women.

A new model for providing cell-free DNA and risk assessment for chromosome abnormalities in a public hospital setting.

OBJECTIVE: Cell-free DNA (cfDNA) offers highly accurate noninvasive screening for Down syndrome. Incorporating it into routine care is complicated. We present our experience implementing a novel program for cfDNA screening, emphasizing patient education, genetic counseling, and resource management. STUDY DESIGN: Beginning in January 2013, we initiated a new patient care model in which high-risk patients for aneuploidy received genetic counseling at 12 weeks of gestation. Patients were presented with four pathways for aneuploidy risk assessment and diagnosis: (1) cfDNA; (2) integrated screening; (3) direct-to-invasive testing (chorionic villus sampling or amniocentesis); or (4) no first trimester diagnostic testing/screening. Patients underwent follow-up genetic counseling and detailed ultrasound at 18-20 weeks to review first trimester testing and finalize decision for amniocentesis. RESULTS: Counseling and second trimester detailed ultrasound were provided to 163 women. Most selected cfDNA screening (69%) over integrated screening (0.6%), direct-to-invasive testing (14.1%), or no screening (16.6%). Amniocentesis rates decreased following implementation of cfDNA screening (19.0% versus 13.0%, P < 0.05). CONCLUSION: When counseled about screening options, women often chose cfDNA over integrated screening. This program is a model for patient-directed, efficient delivery of a newly available high-level technology in a public health setting. Genetic counseling is an integral part of patient education and determination of plan of care.

Evaluation of non-invasive prenatal testing (NIPT) for aneuploidy in an NHS setting: a reliable accurate prenatal non-invasive diagnosis (RAPID) protocol.

BACKGROUND: Non-invasive prenatal testing (NIPT) for aneuploidies is now available through commercial companies in many countries, including through private practice in the United Kingdom (UK). Thorough evaluation of service delivery requirements are needed to facilitate NIPT being offered more widely within state funded healthcare systems such as the UK's National Health Service (NHS). Successful implementation will require the development of laboratory standards, consideration of stakeholder views, an analysis of costs and development of patient and health professional educational materials. METHODS/DESIGN: NIPT will be offered in an NHS setting as a contingent screening test. Pregnant woman will be recruited through six maternity units in England and Scotland. Women eligible for Down's syndrome screening (DSS) will be informed about the study at the time of booking. Women that choose routine DSS will be offered NIPT if they have a screening risk ≥ 1:1000. NIPT results for trisomy 21, 18, 13 will be reported within 7-10 working days. Data on DSS, NIPT and invasive testing uptake, pregnancy outcomes and test efficacy will be collected. Additional data will be gathered though questionnaires to a) determine acceptability to patients and health professionals, b) evaluate patient and health professional education, c) assess informed choice in women accepting or declining testing and d) gauge family expenses. Qualitative interviews will also be conducted with a sub-set of participating women and health professionals. DISCUSSION: The results of this study will make a significant contribution to policy decisions around the implementation of NIPT for aneuploidies within the UK NHS. The laboratory standards for testing and reporting, education materials and counselling strategies developed as part of the study are likely to underpin the introduction of NIPT into NHS practice. NIHR PORTFOLIO NUMBER: 13865.