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Please cite this paper as: Scheffer P, Ait Soussan A, Verhagen O, Page-Christiaens G, Oepkes D, de Haas M, van der Schoot C. Noninvasive fetal genotyping of human platelet antigen-1a. BJOG 2011;118:1392-1395. We describe a reliable noninvasive fetal human platelet antigen (HPA)-1a genotyping assay on a real-time polymerase chain reaction (PCR) platform using cell-free fetal DNA isolated from maternal blood. Nonspecific amplification of maternal cell-free DNA is overcome by pre-PCR digestion of the cell-free DNA with the Msp1 restriction enzyme. Noninvasive fetal HPA-1a genotyping offers a safe method for alloimmunised pregnant women to determine whether their fetus is at risk of fetal or neonatal alloimmune thrombocytopenia (FNAIT) and whether interventions to prevent intracranial haemorrhage are required. The availability of this test is relevant to the ongoing debate on screening pregnancies for HPA-1a-mediated FNAIT. [ABSTRACT FROM AUTHOR]

Introduction The efficacious analysis of fetal loci involving point mutations from circulatory fetal DNA in maternal plasma is hindered by the preponderance of maternal DNA. It has recently been shown that the size difference between fetal and maternal DNA species can be used for the selective enrichment of circulatory fetal DNA in maternal plasma. We have now tested this approach for the detection of a fetal point mutation in the fibroblast growth factor receptor 3 (FGFR3) gene that causes achondroplasia. Methods Circulatory DNA was extracted from maternal plasma and size-fractionated by agarose gel electrophoresis. The fraction with a size less than 300 bp was examined by a touchdown PCR assay specific for the FGFR3 gene, and the mutation was identified by SfcI restriction analysis. Result Our analysis indicated that although the fetal mutation was discernible in the analysis of total plasma DNA, the result using size-fractionated DNA was much more evident. Conclusion The enrichment of circulatory fetal DNA in maternal plasma by size-fractionation facilitates the detection of subtle feto-maternal genetic differences, such as those involving point mutations. This approach can easily be extended for the non-invasive prenatal determination of other fetal loci. (190) Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The practice of prenatal screening is undergoing important changes as a result of the introduction of genomic testing technologies at different stages of the screening trajectory. It is expected that eventually it will become possible to routinely obtain a comprehensive 'genome scan' of all fetuses. Although this will still take several years, there are clear continuities between present developments and this future scenario. As this review shows, behind the still limited scope of screening for common aneuploidies, a rapid widening of the range of conditions tested for is already taking shape at the invasive testing stage. But the continuities are not just technical; they are also ethical. If screening for Down's syndrome is a matter of providing autonomous reproductive choice, then why would providing the choice to have a full fetal genome scan be something entirely different? There is a clear need for a sustainable normative framework that will have to answer three challenges: the indeterminateness of the autonomy paradigm, the need to acknowledge the future child as an interested stakeholder, and the prospect of broad-scope genomic prenatal screening with a double purpose: autonomy and prevention., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To evaluate the diagnostic performance of noninvasive fetal blood group genotyping., Design: Descriptive analysis., Setting: Dutch national reference laboratory for pregnancies complicated by alloimmunisation., Population: All consecutive alloimmunised pregnant women for whom fetal blood group genotyping of rhesus D, c, E or of K in maternal plasma was performed from 2003 up to 2010., Methods: The test results of each individual assay were collected. Real-time polymerase chain reaction was performed for RHD exon 5 and RHD exon 7, or the specific allele of the RHCE or KEL gene. A stringent diagnostic algorithm was applied. In the case of a negative result, the presence of fetal DNA was ascertained by the analysis of the Y chromosome-specific SRY gene or other paternal genetic markers. Results were compared with available serology after birth or genotyping results of amniotic fluid cells., Main Outcome Measures: Percentage of conclusive test results and diagnostic accuracy., Results: A total of 362 tests was performed (D: n = 168; c: n = 49; E: n = 85; K: n = 60). The median gestational age was 17 weeks (range 7-38 weeks). In 351 women (97%), a test result was issued: in seven samples, the presence of fetal DNA could not be confirmed; in two samples, non-specific amplification in the K assay led to an inconclusive result; in two samples, a maternal silent RHD gene prevented fetal RHD genotyping. No false-positive or false-negative results were found among those women for whom cord blood serology or genotyping results of amniotic fluid cells were available (n = 212)., Conclusions: Noninvasive fetal blood group genotyping is accurate and applicable in a clinical diagnostic setting., (© 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG.)

We describe a reliable noninvasive fetal human platelet antigen (HPA)-1a genotyping assay on a real-time polymerase chain reaction (PCR) platform using cell-free fetal DNA isolated from maternal blood. Nonspecific amplification of maternal cell-free DNA is overcome by pre-PCR digestion of the cell-free DNA with the Msp1 restriction enzyme. Noninvasive fetal HPA-1a genotyping offers a safe method for alloimmunised pregnant women to determine whether their fetus is at risk of fetal or neonatal alloimmune thrombocytopenia (FNAIT) and whether interventions to prevent intracranial haemorrhage are required. The availability of this test is relevant to the ongoing debate on screening pregnancies for HPA-1a-mediated FNAIT., (© 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG.)

Genetic cancer syndromes have identical clinical severity, limited therapeutic options, reduced life expectancy, and risks of genetic transmission, as do other genetic or congenital diseases for which prenatal genetic diagnosis or preimplantation genetic diagnosis (PGD) is allowed in the Netherlands. That was implied in the certification of one Dutch PGD centre at Maastricht University Hospital by the Dutch Ministry of Health, Welfare and Sport in 2003. A report by the Health Council of the Netherlands in 2006 confirmed this view with scientific and ethical evaluation. However, in 2006 the State Secretary for Health strongly objected to PGD for cancer, and disease risks of 50-100% for gene carriers, i.e. for highly, but not always fully penetrant genes. In 2006, the Maastricht centre discontinued PGD for cancer and couples were referred to other countries; prenatal genetic diagnosis remained available, however. On 26 May 2008, the present State Secretary proposed to parliament that the Health Council of the Netherlands report from 2006 be followed. This once again clashed with the fears of some Christian parties for a slippery slope and embryo selection for 'only a risk and not certainty of disease'. Yet no firm evidence for the existence of such a slope has been found. The Dutch framework for handling the ethical and medical evaluation of new reproductive and genetic technologies by the Health Council of the Netherlands Advisory Committees, professional and patient organisations, and the Ministry, has functioned for over 30 years without leading to any wrongdoing. There is no actual need for a new government body to license genetic tests on a case-by-case or per disease basis.

Objective: Determination of factors related to the need for transfusion in premature infants., Design: Descriptive., Method: The need for transfusion in premature infants was determined in 2 academic centres: University Medical Center Utrecht and Leiden University Medical Center, The Netherlands. The data had been acquired in another study. The factors under study were: hospital, pregnancy duration, birth weight, gender, time of clamping of the umbilical cord, total volume of blood sampled for diagnostic purposes, number of days of mechanical ventilation, total duration of admission and duration of the admission to the Neonatal Intensive care unit. Both hospitals followed the national interdisciplinary practice guideline 'Blood transfusion'., Results: The total volume ofsampled blood for diagnosis, the duration of the mechanical ventilation and the admission period were related to a greater need for transfusion. On the other hand, the chance of transfusions diminished with longer pregnancy duration or increased birth weight. The difference in need for blood transfusion between both centres was significant. The total volume of transfused erythrocytes showed a strong correlation with the volume sampled for diagnostic procedures., Conclusion: Anaemia in neonates is strongly related to the amount of blood taken for diagnostic procedures. Alternatives for blood transfusions in premature infants, and consequently for the reduction of the number of donors per child, are to be sought in delayed clamping of the umbilical cord, use of erythropoietin and use ofautologous umbilical cord blood.

The Health Council of the Netherlands has published an advisory report on neonatal screening in view of developments in diagnostics, therapy and the prevalence of neonatal diseases. Currently it involves screening for phenylketonuria, congenital hypothyroidism and congenital adrenal hyperplasia. Because screening may lead to considerably better outcomes in affected newborns, the council recommends expanding current screening to include medium-chain acyl-CoA dehydrogenase deficiency, sickle-cell disease and 12 other rare disorders: biotinidase deficiency, galactosaemia, glutaricaciduria type I, HMG-CoA lyase deficiency, holocarboxylase-synthetase deficiency, homocystinuria, isovaleric-acidaemia, long-chain hydroxyacyl-CoA dehydrogenase deficiency, maple syrup urine disease, 3-methylcrotonyl-CoA carboxylase deficiency, tyrosinaemia I and very-long-chain acyl-CoA dehydrogenase deficiency. A better detection method for cystic fibrosis must be developed before it is included in screening to restrict the number of sweat-test referrals of unaffected newborns. The council recommends providing information on neonatal screening during pregnancy and gives special attention to the possibility of detecting carriership in the parents.