Laboratory Guidelines for Detection, Interpretation, and Reporting of Maternal Cell Contamination in Prenatal Analyses

Abstract

This document summarizes laboratory guidelines for the detection, interpretation, and reporting of maternal cell contamination in prenatal analyses.

Whole Gene Sequencing Based Screening Approach to Detect β-Thalassemia Mutations

“…Several studies on hemoglobinopathies and thalassemia have been conducted in various states and population of India by using chromatography based methods [16][17][18][19]. Occurance of thalassemia in India is up to 3%, but in some communities like Sindhis, Punjabis, Lohanas, Kutchi Bhanushalis, Jains and Bohris have a higher prevalence 4-17% [3,8,18,[20][21][22][23][24]. These chromatography based methods can be used to detect hemoglobinopathies in the blood samples but not for detecting prenatal cases.…”

“…The presence of MCC in fetal samples can lead to misdiagnosis when using molecular techniques to detect pathogenic variations. In order to provide the correct prenatal results, the possibility of the presence of contaminating maternal or co-fetal material in AF or CVS sample should be ruled out [24]. In present study, we have used the method described by Batanian et al to detect MCC in the fetal sample [16].…”

Defining the impact of maternal cell contamination on the interpretation of prenatal microarray analysis

“…15 If MCC studies pose a challenge (e.g., financially or due to a lack of a maternal sample), aCGH results from a male fetus may sometimes still be interpreted, as data from the array experiment can be used to exclude interfering levels of MCC. For the most accurate interpretation of how MCC may affect microarray results, the independent methodology used to confirm the presence of MCC should be quantitative.…”

“…1,8 However, when observing blood in amniocyte pellets and seeing only normal female cells on rapid aneuploidy screening by polymerase chain reaction-based methods or fluorescence in situ hybridization, some cytogenetic laboratories may place cautionary notes on reports. [2][3][4][9][10][11] In contrast to traditional cytogenetic analysis, MCC analysis for prenatal molecular testing for single-gene disorders has been recommended by several genetic societies (the American College of Medical Genetics and Genomics, 12 the UK Clinical Molecular Genetics Society, 13 and the Canadian College of Medical Geneticists 7,14 ) and the Association for Molecular Pathology 15 , although not all labs consistently follow this recommendation. 8 These societies recommend that labs performing prenatal molecular testing understand how MCC may affect detection of normal and abnormal results for each assay.…”

“…Recently, the Association for Molecular Pathology recommended MCC analysis for all prenatal samples undergoing molecular testing and for those undergoing molecular cytogenetic analyses such as microarraybased comparative genomic hybridization (aCGH). 15 Microarray analysis is a relatively recent tool for prenatal diagnosis, with recommendations focused on using this technology for pregnancies with abnormal ultrasound findings and normal chromosome analysis. 16 This algorithm usually requires…”