All but one of these, however, required only two markers to be informative. Maternal cell contamination: a problem in amniocentesis. Ten laboratories tested CVS cultures but not direct CVS. A positive apt test would mean that the blood is either due to gastrointestinal or pulmonary bleeding from the neonate. Individual methods for determination of the lower limit of detection were not disclosed. [1][2], The test was developed by Leonard Apt (1922–2013),[3] an American pediatric ophthalmologist. February 23, This would reduce the number of MCC assays in cases of testing for autosomal recessive conditions by almost 50%, if all cases of multiple gestation and those in which both parents carry the same mutation would still receive MCC testing. Some caveats in PCR-based prenatal diagnosis on direct amniotic fluid versus cultured amniocytes. Genetics Test Information Provides information that may help with selection of the correct genetic test or proper submission of the test request. TAT: 24-72 hrs. It has been modified to distinguish fetal from maternal hemoglobin in blood samples from any source. Confined placental trisomy 7: pitfall for cystic fibrosis prenatal diagnosis. Although the presence of MCC does not always lead to diagnostic errors, if such errors do occur, the consequences in the prenatal setting could result in an inappropriate termination of a pregnancy. Diagnostic mid trimester amniocentesis: how safe?. By continuing you agree to the, https://doi.org/10.2353/jmoldx.2007.070017, Testing for Maternal Cell Contamination in Prenatal Samples, View Large MCC testing was performed in the majority of molecular diagnostic laboratories, but guidelines for standardization are needed to ensure optimal and accurate prenatal patient care. The aim of this study was to identify current diagnostic practices in the absence of comprehensive practice guidelines. CONCLUSIONS: For heavily bloodstained … Another example of variation between laboratories was in the reported lower level of detection for MCC assays, which varied from 1 to 20% (. Conclusions. History. Even low levels of MCC may interfere with correct molecular diagnoses because PCR can, under optimized circumstances, detect a subpopulation of cells at levels of 0.1%. It consists of three parts: Utilities for: Working with VCF files; Using a pretrained model to recalibrate the genotype (GATK output) of a contaminated sample These early studies focused on 16S ribosomal RNA (rRNA) sequences which are relatively … Synonyms: MCC. QF-PCR analysis has established a higher incidence of maternal cell contamination … Of note, however, this laboratory had only recently initiated MCC testing and had not yet encountered MCC in a prenatal sample. The incidence of recognized cases of … Fetal hemoglobin is resistant to alkali (basic) denaturation, whereas adult hemoglobin is susceptible to such denaturation. The presence of maternal cells does not always lead to a prenatal diagnostic error. Nonradioactive PCRs were performed on 30 sets of prenatal tissue using VNTRs as primers. If the assay was uninformative by their own criteria, additional markers were added by two thirds of the laboratories, whereas one third did not expand the assay. [Maternal cell contamination of cultures of spontaneous abortion fibroblasts: importance for cytogenetic analysis of embryonic lethality]. Alkali denaturation test; Purpose: differentiate neonatal from maternal blood: The alkali denaturation test, also known as A or Apt test, is a medical test used to differentiate fetal or neonatal blood from maternal blood found in a newborn's stool or vomit, or from maternal … Reporting time. Maternal blood contains adult hemoglobin composed of two alpha and two beta subunits (aka hemoglobin A or HbA; i.e., normal adult hemoglobin). Heath, K. Abruptio Placentae. The vast majority of participating laboratories used two or three markers to determine that the assay was informative. Twelve laboratories charged less than $300, and one laboratory, which uses a variable number of markers (depending on informativeness), charged less than $300 when less than eight markers were used and between $300 and $500 when 13 markers were used. Maternal Cell Contamination, B Overview Useful For Ruling out the presence of maternal cell contamination within a fetal specimen This test is required for all prenatal testing performed in Mayo's molecular and biochemical genetics laboratories Genetics Test Information Required in conjunction with molecular and biochemical prenatal testing only. Maternal cell contamination (MCC) affects 0.3-0.7% and 1-2.5% of AF and CVS specimens, respectively (Steed et al. … A negative Apt test would indicate that the blood is of maternal origin, suggesting that the neonate swallowed or aspirated maternal blood, either during delivery or during breastfeeding (e.g., from breast fissures). (1.0 mL min. Methods: A prospective observational study was performed. The sample is next centrifuged for several minutes. of maternal cell contamination (MCC) confounds isolation of MSC from placenta, and their mixed origin confuses the stem cell com-munity. One hundred sixty‐two cytogeneticists and medical geneticists were invited to participate, and data were collected from 71 laboratories, representing 91,131 amniocenteses. Additional Info: Maternal Cell Contamination, Blood Maternal Cell Contamination Analysis. Thus, more information can be gleaned from an expanded assay with multiple markers associated with a requirement of several informative markers. View and print a requisition form for this test. Fetal and maternal pMSC have been compared to MSC isolated from amniotic membrane (fetal) and decidua (maternal). This page was last edited on 31 December 2020, at 20:04. As a consequence of allelic identity between mother and fetus, an MCC assay can be uninformative. Venes, D. Taber's Cyclopedic Medical Dictionary - 20th Ed. This phenomenon of maternal cell contamination (MCC) confounds isolation of MSC from placenta, and their mixed origin confuses the stem cell community. Key words Maternal cell contamination Prenatal diagnosis Microsatellite markers Short tandem repeats Genotyping Sample identity This is a preview of subscription content, log … The Apt test can also be used to detect the presence of fetal blood in the maternal circulation in cases of suspected fetal-maternal hemorrhage. 4 days - 3 weeks. The different modes of inheritance associated with genetic conditions deserve brief consideration because they may be impacted by MCC in different ways. A simple and effective approach for detecting maternal cell contamination in molecular prenatal diagnosis. This large survey of 35 US diagnostic laboratories that perform prenatal testing demonstrates that the majority perform MCC testing in conjunction with the diagnostic test. The color of the fluid is assessed after 2 minutes. in 5-Minute Clinical Consult, 15th ed. The single laboratory that required four informative markers used an assay developed in-house with up to 10 markers, adding them as needed to reach a status of informative results. DOI: https://doi.org/10.2353/jmoldx.2007.070017. View … Lipponcott Williams & Wilkins, Philadelphia, PA. 2007. One of the risks associated with prenatal testing is maternal cell contamination (MCC), which can occur when a fetal specimen comes into contact with maternal blood or tissue. comment. A Comprehensive Survey of Current Diagnostic Practices in 35 Molecular Diagnostic Laboratories, CYP1B1 Mutation Profile of Iranian Primary Congenital Glaucoma Patients and Associated Haplotypes, A Comparative Study of Five Technologically Diverse CFTR Testing Platforms. State funding for Victorian patients. Maternal cell contamination of chorionic villi (CV) samples used for first trimester prenatal diagnosis can cause obvious and/or unrecognized diagnostic dilemmas. Four laboratories did not perform MCC testing at all. The fetal hemoglobin will appear as a pinkish color under the microscope while the adult hemoglobin will appear as a yellow-brownish color. Lab/Phone: 330-543-8722. Maternal cell contamination in uncultured amniotic fluid. A negative test indicates that the blood is of maternal origin. Sixty percent of participating laboratories performed testing on direct and cultured amniotic fluid, whereas forty percent tested cultured cells only. CPT Code: N/A. To determine the pure fetal origin of all prenatal specimens undergoing genetic analysis, it is recommended that MCC analysis be … Implication of maternal-cell contamination in the clinical banking of umbilical cord blood. A simple VNTR-PCR method for detecting maternal cell contamination in prenatal diagnosis. The initial 2-3 ml of amniotic fluid withdrawn during amniocentesis was divided into direct analysis (uncultured) and cultured samples. For conditions with autosomal recessive inheritance, one quarter of the tested fetuses are expected to carry the maternal mutation and cannot be distinguished from the mother by mutation analysis alone. Thus, all prenatal samples should be subjected to testing for maternal cell contamination. Percutaneous umbilical cord blood sampling (PUBS), also called cordocentesis, fetal blood sampling, or umbilical vein sampling is a diagnostic genetic test that examines blood from the fetal umbilical cord to detect fetal abnormalities. 2005; Stojilkovic-Mikic et al. Domino, FJ editor. F. A. Davis Company, Philadelphia, PA. 2005. 2007. Twenty-nine laboratories commented on their billing practice. Although MCC testing of fetal samples is recommended in guidelines by the American College of Medical Genetics, only 60% of surveyed laboratories performed it without exception. Conventional sequencing begins with a culture of identical cells as a source of DNA.However, early metagenomic studies revealed that there are probably large groups of microorganisms in many environments that cannot be cultured and thus cannot be sequenced. Ruling out the presence of maternal cell contamination within a fetal specimen . AF and CVS have their respective advantages and disadvantages, reflected in the spectrum of accepted sample types by the surveyed diagnostic laboratories (, Even though MCC has been recognized as a potential cause of misdiagnosis in prenatal testing, our survey of 35 clinical diagnostic laboratories indicated that these laboratories use different assays and MCC testing practices. Image, Download Hi-res Genetics and Genomics; Laboratory Services; Cost. The number of identity markers included in individual tests was comparable between commercial and homebrew MCC assays with 4 to 16, and 2 to 13, respectively. Contamination with maternal cells can result in interpretation errors of diagnostic tests, including mutation analyses and detection of aneuploidy by fluorescent in situ hybridization. The survey included questions about sample requirements, test indications, assay type, test performance and limitations, criteria and management of uninformative test results, reporting, and billing. Fetal hemoglobin will stay pink and adult hemoglobin will turn yellow-brown since adult hemoglobin is less stable and will convert to hematin which has a hydroxide ligand.[5]. [4], The Apt test is most commonly used in cases of vaginal bleeding late during pregnancy (antepartum haemorrhage) to determine if the bleeding is from the mother or the fetus. The blood is mixed with a small amount of sterile water to cause hemolysis of the RBCs, yielding free hemoglobin. ML-maternal-cell-contamination. Seven amniotic fluid samples (2.8%) showed maternal cell contamination in cultured material. Especially when the percentage of maternal cells contaminating the prenatal sample is very low (∼1%), the maternal allele may not be detectable in every single marker. An Informed Consent for Genetic Testing (Supply T576) is available in Special Instructions. Overall, however, fewer markers were used in homebrew assays. Although the number of markers used is somewhat arbitrary, the inclusion of a low number of markers may provide a false sense of security if MCC is not detected. Detection of maternal cell contamination in amniotic fluid cell cultures using fluorescent labelled microsatellites. Contamination of a CVS sample with cells of maternal origin may result in analysis of the maternal rather than the fetal karyotype or genotype, especially when the sample size is small. Four laboratories provided MCC testing at no cost at all. A variety of commercially available DNA typing assays (by Applied Biosystems, Foster City, CA, and Promega, Madison, WI) were used by 71.4% (20 of 28) of participants, whereas 28.6% (8 of 28) had developed a method in their own laboratory. Thus, the samples are essentially irreplaceable, and often only small amounts or suboptimal specimens are submitted. Of these, 58.6% (17 of 29) billed separately, and 27.6% (8 of 29) billed for the MCC test as an integral part of the performed prenatal test. If MCC is present, the maternal DNA may … 3177. The effectiveness of variable number tandem repeats (VNTRs) was evaluated in the detection of maternal cell contamination. Address reprint requests to Iris Schrijver, M.D., Department of Pathology and Pediatrics, L235, Stanford University Medical Center, 300 Pasteur Dr., Stanford, CA 94305, Departments of Pathology and Pediatrics, Stanford University School of Medicine, Stanford, California, Department of Pathology, Stanford University School of Medicine, Stanford, California. The purpose of this investigation is to assess the frequency of maternal cell contamination (MCC) in chorionic villus samples and to evaluate selected parameters which might predict where contamination is … Copyright © 2021 Elsevier Inc. except certain content provided by third parties. Methods: Quantitative fluorescence-polymerase chain … This small amount of contamination should have negligible effects on the assessment of DNA or RNA. EDTA whole blood) Maternal Cell Contamination, Blood Test (LAB4139) must be ordered with Maternal Cell Contamination Analysis Test (LAB 4138). The aim of this study was to identify current diagnostic practices in the absence of comprehensive practice guidelines. This is particularly of concern with sensitive polymerase chain reaction (PCR)-based molecular assays that may lead to a positive result based on the presence of a very small amount of mutation-positive maternal cells. Required in conjunction with … This test is required for all prenatal testing performed in Mayo's molecular and biochemical genetics laboratories. However, it also illustrates that clinical practice is not yet standardized. We use cookies to help provide and enhance our service and tailor content and ads. But these anatomical locations have markedly different niches and functions in vivo, whereas none compare fetal and maternal … Increasing knowledge of inherited genetic conditions, the characterization of associated genes, and continuing advances in diagnostic techniques have enabled genetic testing of prenatal samples in cytogenetic and molecular laboratories. The potential presence of maternal cell contamination (MCC) in chorionic villus or amniotic fluid samples poses a serious preanalytical risk for prenatal misdiagnosis. Direct, as well as cultured CV samples were tested in 67.7% of those facilities (21 of 31). Distribution of accepted specimen types in 35 molecular diagnostic laboratories. Please enter a term before submitting your search. The 19 laboratories that provided a report for MCC assays with uninformative results and with no evidence of MCC in any of the markers tested, reported to sign out such results as “uninformative” or “equivocal.” A comment was added reflecting that MCC was unlikely but could not be excluded or stating that the results are consistent with fetally derived cells and that no MCC was detected. [Article in Russian] Nikitina TV, Lebedev IN, Sukhanova NN, Sazhenova EA, Nazarenko SA. A second genotype, interpreted as maternal cell contamination, was identified in direct and/or cultured preparations in 9.1% of samples, 17.8% of which were not bloodstained. The problem of contamination of amniotic fluid cultures with maternal cells is described in 3 cases. The combination of two VNTRs (YNZ22 and APOB) provided information on all 30 cases, distinguishing maternal-fetal genotype patterns and detecting maternal cell contamination … Mulcahy MT, Jenkyn J. PMID: 965000 [PubMed - indexed for MEDLINE] Published by Elsevier Inc. All rights reserved. "My two-week-old daughter is throwing up blood", Obituary: Leonard Apt, 90, doctor-scientist who gave gift of vision to millions of children, "An easy-to-use method for detecting fetal hemoglobin-- a test to identify bleedingfrom vasa previa", Percutaneous umbilical cord blood sampling, Mean corpuscular hemoglobin concentration, https://en.wikipedia.org/w/index.php?title=Alkali_denaturation_test&oldid=997496046, Articles with unsourced statements from July 2020, Creative Commons Attribution-ShareAlike License, differentiate neonatal from maternal blood, A positive test would indicate that blood is of fetal origin, and could be due to. Purpose: The purpose of this study is to evaluate the incidence of maternal cell contamination (MCC) in the first few milliliters of amniotic fluid withdrawn during amniocentesis. [citation needed]. Prenatal diagnosis of genetic disorders, however, is often not straightforward. The laboratory should be familiar with the band intensities of specific primers and be alert to novel bands or changes in band intensities. This question was answered by 27 laboratories. For any prenatal sample, a larger volume or tissue amount, older gestational age, and highly robust prenatal assays are preferable. The reported lower limit of detection for MCC in US diagnostic laboratories. 2002;Steinberg et al. In CVS and abortus samples, the culturing process increases the risk of detectable MCC given the colocalization of maternal and fetal cell lineages in the placenta. Rapid prenatal diagnosis of chromosomal aneuploidies by fluorescence in situ hybridization: clinical experience with 4,500 specimens. LabCorp buccal swab kits can be ordered using PeopleSoft No. simulated_maternal_cell_contamination Identifier-ark ark:/13960/t91913x1w Scanner Internet Archive HTML5 Uploader 1.6.4. plus-circle Add Review. For heavily bloodstained amniotic fluid samples, a maternal blood specimen may help interpret the results of rapid trisomy testing, followed by confirmation of the fetal origin of cultured cells. The only practice guidelines available for the assessment of MCC during prenatal testing are described in the 2006 edition of Standards and Guidelines for Clinical Genetics Laboratories at, Laboratories in the United States were selected for the study based on their Genetests (, All participating molecular diagnostic laboratories offered AF testing. Finally, at the time of the survey, a single laboratory charged between $500 and $800. When biopsying a fetal tissue like chorionic villi or amniotic fluid, there is a chance of getting some maternal material that could contaminate the fetal specimen and might lead to a misdiagnosis. Thus, all prenatal samples should be subjected to testing for maternal cell contamination. DNA analysis intended to identify a species, rather than an individual, is called DNA barcoding.. DNA profiling is a forensic technique in criminal investigations, comparing criminal suspects' profiles to DNA evidence so as to assess the likelihood of their involvement … The quantity of material requested for direct AF testing ranged from 2 to 25 ml, whereas the sample requirements for direct CVS testing ranged from no minimum to 30 mg (, Testing for MCC in prenatal samples is considered the standard of care as described in the 2006 edition of Standards and Guidelines for Clinical Genetics Laboratories at. Only three laboratories used four markers or fewer (10.7%). The majority of participating laboratories also offered CVS testing (88.6%, 31 of 35). Therefore, exposing the blood specimen to sodium hydroxide (NaOH) will denature the adult but not the fetal hemoglobin. On the one hand, amniotic fluid (AF) or a chorionic villus sample (CVS) is obtained by the obstetrician/gynecologist during an invasive procedure that is associated with potential pregnancy loss. Thus, routine performance of this procedure seems paramount to achieving and maintaining competence. Seven amniotic fluid samples (2.8%) showed maternal cell contamination in cultured material. To eliminate errors in prenatal testing as much as possible, we recommend that MCC testing be performed on all prenatal samples and for all modes of inheritance. This emphasizes the need for specific guidelines to ensure consistent and optimal prenatal patient care. Fetal and maternal blood supply are typically connected in utero with one vein and two arteries to the fetus. Be the first one to write a review. Forms: New York Clients-Informed consent is required. By continuing you agree to the Use of Cookies. Maternal cell contamination studies (MCC) are performed in the prenatal testing arena to ensure the fetally derived sample is not compromised by maternal cells. Two samples (0.65%) were mosaic for an aneuploidy cell line. Objectives: To establish the genotype of cultured cells from a cohort of amniotic fluid and chorionic villus samples, and compare this genotype with that obtained from uncultured material from the same sample, in order to assess the frequency and significance of maternal cell contamination of prenatal samples. A nationwide survey has been carried out to establish the incidence and factors determining maternal cell contamination (MCC) of amniotic fluid cultures. This is done using quantitative fluorescent PCR (QF-PCR) of short tandem repeat (STR) markers. Category. This level is routinely … Please document on the request form or electronic order that a copy is on file. Clinical practice questionnaire, used in phone interviews. One additional laboratory was in this price range. The reported lower limit of MCC detection ranged from 1 to 20% but was not determined in all laboratories. Of the 17 laboratories that charged for MCC testing separately, 15 provided information about pricing. The frequency of maternal cell contamination varies considerably due to sampling protocol, operator and culturing of cells from the fetal sample. But these anatomical locations have markedly different niches and functions in vivo, whereas none compare fetal and maternal … The pink hemoglobin-containing supernatant is then mixed with 1 mL of 1% NaOH for each 5 mL of supernatant. Of the 28 laboratories that were offering MCC in-house or would offer it very soon and had decided on the content of their reports, four provided only a written report and 23 offered a written report with verbal consultation, as necessary. The reported lower limit of detection for the MCC assays included in this study ranged from 1 to 20% but was not determined in all laboratories (. The utility and efficiency of the algorithm proposed in. DA, direct amniotic fluid; CA, cultured amniotic fluid; DCVS, direct chorionic villus sample; CCVS, cultured chorionic villus sample. 1. The risk of MCC is associated with procedures such as chorionic villus sampling, amniocentesis, or extraction of fetal blood from the umbilical cord (cord blood). … Finally, the Apt test can be used after birth (postpartum hemorrhage) if the newborn has bloody vomiting, bloody stool, or active bleeding from the nasogastric tube. Four were in the process of setting up the assay and had already decided on the sample type they would accept, and three other laboratories sent their samples to a reference laboratory for MCC evaluation. One laboratory, using three to eight identity markers as needed, reported a percentage (75 to 80%) of informative markers instead of a number. The contamination of fetal samples with maternal cells is cause for concern in prenatal testing. Previous studies have shown that such contamination can occur relatively frequently, estimated at 2–20% of collected samples, but it makes up a very small fraction of fetal blood, with ~10 −4 to 10 −5 fetal nucleated cells estimated as maternal [7,8,9,10]. Thirty-five clinical molecular laboratories that conduct prenatal testing agreed to participate in a clinical practice survey. Not surprisingly, the latter testing facilities all used nine markers or more (up to 16). … The lower limit of detection is indicated in the legend on the right and by the columns of the histogram, whereas the number of laboratories for each category is listed on top of the columns. MCC testing practice for 34 US laboratories. Maternal Cell Contamination (MCC) study is important test which provides assurance that the results of molecular analyses such as sequencing and microarray performed on fetal specimens are accurate and are not influenced by maternal DNA. If cultured cells are needed, an additional 7-12 days may be required. Accepted: Since the test is only a qualitative determination of the presence of fetal hemoglobin in maternal blood, the quantitative Kleihauer-Betke test is more commonly used. In practice, the Apt test may not be done when there is suspicion of vasa previa, because the time to fetal collapse with bleeding from vasa previa is often very short. Uninformative results had not been encountered by 12 laboratories. Maternal cell contamination of amniotic fluid samples obtained by open needle versus trocar technique of amniocentesis. One example of variation between laboratories was in the number of markers in the MCC assay, which ranged from 2 to 16. MATCC / Maternal Cell Contamination, Molecular Analysis must be ordered on both the prenatal and maternal specimens under separate order numbers. One survey question addressed the type of MCC assay used in each laboratory. In addition, three of the four laboratories that were developing MCC testing had decided on their approach, and one of three laboratories that sent out their samples for MCC testing was readily familiar with the method used by their reference laboratory. Fetal blood contains fetal hemoglobin composed of two alpha and two gamma subunits (aka hemoglobin F or HbF; i.e., normal fetal hemoglobin). Although some laboratories request samples from both the mother and the father, only the maternal sample is strictly required to perform MCC testing, also avoiding issues of potential nonpaternity. Phone: 1300 11 8247 Email: [email protected] Specimen Requirements. Sixty percent (21 of 35) performed diagnostic prenatal testing on direct and cultured AF, whereas 40% (14 of 35) used only cultured AF cells. We thank all participating laboratories for their participation in this study. Fetal and maternal pMSC have been compared to MSC isolated from amniotic membrane (fetal) and decidua (maternal). It has been proposed to perform the diagnostic assay first and only to proceed to MCC testing if the fetal sample appears positive for the known maternal mutation. Operator experience and sample quality in genetic amniocentesis. Rapid prenatal diagnosis of trisomy 21 in 5049 consecutive uncultured amniotic fluid samples by fluorescence in situ hybridisation (FISH). The potential presence of maternal cells in CVS or AF samples poses a significant preanalytical risk for prenatal misdiagnosis.